diff --git a/docs/pages/api-docs/popover.json b/docs/pages/api-docs/popover.json
index 4c034015a04250..b4bb01dffceee3 100644
--- a/docs/pages/api-docs/popover.json
+++ b/docs/pages/api-docs/popover.json
@@ -31,6 +31,7 @@
       "type": { "name": "shape", "description": "{ component?: element type }" },
       "default": "{}"
     },
+    "sx": { "type": { "name": "object" } },
     "transformOrigin": {
       "type": {
         "name": "shape",
@@ -55,6 +56,6 @@
   "filename": "/packages/material-ui/src/Popover/Popover.js",
   "inheritance": { "component": "Modal", "pathname": "/api/modal/" },
   "demos": "<ul><li><a href=\"/components/menus/\">Menus</a></li>\n<li><a href=\"/components/popover/\">Popover</a></li></ul>",
-  "styledComponent": false,
+  "styledComponent": true,
   "cssComponent": false
 }
diff --git a/docs/translations/api-docs/popover/popover.json b/docs/translations/api-docs/popover/popover.json
index 169f18cde52cb6..de0491a8b129e1 100644
--- a/docs/translations/api-docs/popover/popover.json
+++ b/docs/translations/api-docs/popover/popover.json
@@ -15,6 +15,7 @@
     "onClose": "Callback fired when the component requests to be closed. The <code>reason</code> parameter can optionally be used to control the response to <code>onClose</code>.",
     "open": "If <code>true</code>, the component is shown.",
     "PaperProps": "Props applied to the <a href=\"/api/paper/\"><code>Paper</code></a> element.",
+    "sx": "The system prop that allows defining system overrides as well as additional CSS styles. See the <a href=\"/system/basics/#the-sx-prop\">`sx` page</a> for more details.",
     "transformOrigin": "This is the point on the popover which will attach to the anchor&#39;s origin.<br>Options: vertical: [top, center, bottom, x(px)]; horizontal: [left, center, right, x(px)].",
     "TransitionComponent": "The component used for the transition. <a href=\"/components/transitions/#transitioncomponent-prop\">Follow this guide</a> to learn more about the requirements for this component.",
     "transitionDuration": "Set to &#39;auto&#39; to automatically calculate transition time based on height.",
diff --git a/packages/material-ui/src/Popover/Popover.d.ts b/packages/material-ui/src/Popover/Popover.d.ts
index 7e572794f99f7b..ce77cbf7559c3d 100644
--- a/packages/material-ui/src/Popover/Popover.d.ts
+++ b/packages/material-ui/src/Popover/Popover.d.ts
@@ -1,7 +1,9 @@
 import * as React from 'react';
+import { SxProps } from '@material-ui/system';
 import { InternalStandardProps as StandardProps } from '..';
 import { PaperProps } from '../Paper';
 import { ModalProps } from '../Modal';
+import { Theme } from '../styles';
 import { TransitionHandlerProps, TransitionProps } from '../transitions/transition';
 
 export interface PopoverOrigin {
@@ -103,6 +105,10 @@ export interface PopoverProps
    * @default {}
    */
   PaperProps?: Partial<PaperProps>;
+  /**
+   * The system prop that allows defining system overrides as well as additional CSS styles.
+   */
+  sx?: SxProps<Theme>;
   /**
    * This is the point on the popover which
    * will attach to the anchor's origin.
diff --git a/packages/material-ui/src/Popover/Popover.js b/packages/material-ui/src/Popover/Popover.js
index d403c77fd0d245..42cbefd237fe1b 100644
--- a/packages/material-ui/src/Popover/Popover.js
+++ b/packages/material-ui/src/Popover/Popover.js
@@ -1,19 +1,23 @@
 import * as React from 'react';
 import PropTypes from 'prop-types';
+import clsx from 'clsx';
+import { unstable_composeClasses as composeClasses } from '@material-ui/unstyled';
 import {
   chainPropTypes,
+  deepmerge,
   elementTypeAcceptingRef,
   refType,
   HTMLElementType,
 } from '@material-ui/utils';
-import clsx from 'clsx';
+import experimentalStyled from '../styles/experimentalStyled';
+import useThemeProps from '../styles/useThemeProps';
 import debounce from '../utils/debounce';
 import ownerDocument from '../utils/ownerDocument';
 import ownerWindow from '../utils/ownerWindow';
-import withStyles from '../styles/withStyles';
-import Modal from '../Modal';
 import Grow from '../Grow';
+import Modal from '../Modal';
 import Paper from '../Paper';
+import popoverClasses, { getPopoverUtilityClass } from './popoverClasses';
 
 export function getOffsetTop(rect, vertical) {
   let offset = 0;
@@ -65,26 +69,56 @@ function getAnchorEl(anchorEl) {
   return typeof anchorEl === 'function' ? anchorEl() : anchorEl;
 }
 
-export const styles = {
-  /* Styles applied to the root element. */
-  root: {},
-  /* Styles applied to the Paper component. */
-  paper: {
-    position: 'absolute',
-    overflowY: 'auto',
-    overflowX: 'hidden',
-    // So we see the popover when it's empty.
-    // It's most likely on issue on userland.
-    minWidth: 16,
-    minHeight: 16,
-    maxWidth: 'calc(100% - 32px)',
-    maxHeight: 'calc(100% - 32px)',
-    // We disable the focus ring for mouse, touch and keyboard users.
-    outline: 0,
-  },
+const overridesResolver = (props, styles) => {
+  return deepmerge(styles.root || {}, {
+    [`& .${popoverClasses.paper}`]: styles.paper,
+  });
 };
 
-const Popover = React.forwardRef(function Popover(props, ref) {
+const useUtilityClasses = (styleProps) => {
+  const { classes } = styleProps;
+
+  const slots = {
+    root: ['root'],
+    paper: ['paper'],
+  };
+
+  return composeClasses(slots, getPopoverUtilityClass, classes);
+};
+
+const PopoverRoot = experimentalStyled(
+  Modal,
+  {},
+  {
+    name: 'MuiPopover',
+    slot: 'Root',
+    overridesResolver,
+  },
+)({});
+
+const PopoverPaper = experimentalStyled(
+  Paper,
+  {},
+  {
+    name: 'MuiPopover',
+    slot: 'Paper',
+  },
+)({
+  position: 'absolute',
+  overflowY: 'auto',
+  overflowX: 'hidden',
+  // So we see the popover when it's empty.
+  // It's most likely on issue on userland.
+  minWidth: 16,
+  minHeight: 16,
+  maxWidth: 'calc(100% - 32px)',
+  maxHeight: 'calc(100% - 32px)',
+  // We disable the focus ring for mouse, touch and keyboard users.
+  outline: 0,
+});
+
+const Popover = React.forwardRef(function Popover(inProps, ref) {
+  const props = useThemeProps({ props: inProps, name: 'MuiPopover' });
   const {
     action,
     anchorEl,
@@ -95,7 +129,6 @@ const Popover = React.forwardRef(function Popover(props, ref) {
     anchorPosition,
     anchorReference = 'anchorEl',
     children,
-    classes,
     className,
     container: containerProp,
     elevation = 8,
@@ -114,6 +147,21 @@ const Popover = React.forwardRef(function Popover(props, ref) {
   } = props;
   const paperRef = React.useRef();
 
+  const styleProps = {
+    ...props,
+    anchorOrigin,
+    anchorReference,
+    elevation,
+    marginThreshold,
+    PaperProps,
+    transformOrigin,
+    TransitionComponent,
+    transitionDuration: transitionDurationProp,
+    TransitionProps,
+  };
+
+  const classes = useUtilityClasses(styleProps);
+
   // Returns the top/left offset of the position
   // to attach to on the anchor element (or body if none is provided)
   const getAnchorOffset = React.useCallback(
@@ -379,31 +427,32 @@ const Popover = React.forwardRef(function Popover(props, ref) {
     containerProp || (anchorEl ? ownerDocument(getAnchorEl(anchorEl)).body : undefined);
 
   return (
-    <Modal
+    <PopoverRoot
+      BackdropProps={{ invisible: true }}
+      className={clsx(classes.root, className)}
       container={container}
       open={open}
       ref={ref}
-      BackdropProps={{ invisible: true }}
-      className={clsx(classes.root, className)}
+      styleProps={styleProps}
       {...other}
     >
       <TransitionComponent
         appear
         in={open}
-        timeout={transitionDuration}
         onEntering={handleEntering}
+        timeout={transitionDuration}
         {...TransitionProps}
       >
-        <Paper
+        <PopoverPaper
           elevation={elevation}
           ref={paperRef}
           {...PaperProps}
           className={clsx(classes.paper, PaperProps.className)}
         >
           {children}
-        </Paper>
+        </PopoverPaper>
       </TransitionComponent>
-    </Modal>
+    </PopoverRoot>
   );
 });
 
@@ -548,6 +597,10 @@ Popover.propTypes = {
   PaperProps: PropTypes /* @typescript-to-proptypes-ignore */.shape({
     component: elementTypeAcceptingRef,
   }),
+  /**
+   * The system prop that allows defining system overrides as well as additional CSS styles.
+   */
+  sx: PropTypes.object,
   /**
    * This is the point on the popover which
    * will attach to the anchor's origin.
@@ -595,4 +648,4 @@ Popover.propTypes = {
   TransitionProps: PropTypes.object,
 };
 
-export default withStyles(styles, { name: 'MuiPopover' })(Popover);
+export default Popover;
diff --git a/packages/material-ui/src/Popover/Popover.test.js b/packages/material-ui/src/Popover/Popover.test.js
index 92ed380077c614..697838a8188445 100644
--- a/packages/material-ui/src/Popover/Popover.test.js
+++ b/packages/material-ui/src/Popover/Popover.test.js
@@ -1,12 +1,18 @@
 import * as React from 'react';
 import { expect } from 'chai';
 import { spy, stub, useFakeTimers } from 'sinon';
-import { findOutermostIntrinsic, getClasses, createMount, describeConformance } from 'test/utils';
+import {
+  findOutermostIntrinsic,
+  createMount,
+  createClientRender,
+  describeConformanceV5,
+} from 'test/utils';
 import PropTypes from 'prop-types';
-import Grow from '../Grow';
-import Modal from '../Modal';
-import Paper from '../Paper';
-import Popover, { getOffsetLeft, getOffsetTop } from './Popover';
+import Grow from '@material-ui/core/Grow';
+import Modal from '@material-ui/core/Modal';
+import Paper from '@material-ui/core/Paper';
+import Popover, { popoverClasses as classes } from '@material-ui/core/Popover';
+import { getOffsetLeft, getOffsetTop } from './Popover';
 import useForkRef from '../utils/useForkRef';
 
 const mockedAnchorEl = () => {
@@ -49,27 +55,26 @@ const FakePaper = React.forwardRef(function FakeWidthPaper(props, ref) {
 describe('<Popover />', () => {
   // StrictModeViolation: Not using act(), prefer using createClientRender from test/utils
   const mount = createMount({ strict: false });
-  let classes;
+  const render = createClientRender();
   const defaultProps = {
     open: false,
     anchorEl: () => document.createElement('svg'),
   };
 
-  before(() => {
-    classes = getClasses(
-      <Popover {...defaultProps}>
-        <div />
-      </Popover>,
-    );
-  });
-
-  describeConformance(<Popover {...defaultProps} open />, () => ({
+  describeConformanceV5(<Popover {...defaultProps} open />, () => ({
     classes,
     inheritComponent: Modal,
+    render,
     mount,
+    muiName: 'MuiPopover',
     refInstanceof: window.HTMLDivElement,
+    testDeepOverrides: { slotName: 'paper', slotClassName: classes.paper },
     skip: [
       'componentProp',
+      'componentsProp',
+      'themeDefaultProps',
+      'themeStyleOverrides',
+      'themeVariants',
       // react-transition-group issue
       'reactTestRenderer',
     ],
@@ -83,7 +88,7 @@ describe('<Popover />', () => {
         </Popover>,
       );
       const root = wrapper.find('ForwardRef(Popover) > [data-root-node]').first();
-      expect(root.type()).to.equal(Modal);
+      expect(root.find(Modal).exists()).to.equal(true);
       expect(root.props().BackdropProps.invisible).to.equal(true);
     });
 
@@ -433,7 +438,7 @@ describe('<Popover />', () => {
     it('should warn if anchorEl is not valid', () => {
       expect(() => {
         PropTypes.checkPropTypes(
-          Popover.Naked.propTypes,
+          Popover.propTypes,
           { classes: {}, open: true },
           'prop',
           'MockedPopover',
@@ -444,7 +449,7 @@ describe('<Popover />', () => {
     it('warns if a component for the Paper is used that cant hold a ref', () => {
       expect(() => {
         PropTypes.checkPropTypes(
-          Popover.Naked.propTypes,
+          Popover.propTypes,
           { ...defaultProps, classes: {}, PaperProps: { component: () => <div />, elevation: 4 } },
           'prop',
           'MockedPopover',
diff --git a/packages/material-ui/src/Popover/index.js b/packages/material-ui/src/Popover/index.js
index 44c04deafa71ff..210824f52648b8 100644
--- a/packages/material-ui/src/Popover/index.js
+++ b/packages/material-ui/src/Popover/index.js
@@ -1 +1,4 @@
 export { default } from './Popover';
+
+export { default as popoverClasses } from './popoverClasses';
+export * from './popoverClasses';
diff --git a/packages/material-ui/src/Popover/popoverClasses.d.ts b/packages/material-ui/src/Popover/popoverClasses.d.ts
new file mode 100644
index 00000000000000..dba3bff5ed8ab9
--- /dev/null
+++ b/packages/material-ui/src/Popover/popoverClasses.d.ts
@@ -0,0 +1,7 @@
+import { PopoverClassKey } from './Popover';
+
+declare const popoverClasses: Record<PopoverClassKey, string>;
+
+export function getPopoverUtilityClass(slot: string): string;
+
+export default popoverClasses;
diff --git a/packages/material-ui/src/Popover/popoverClasses.js b/packages/material-ui/src/Popover/popoverClasses.js
new file mode 100644
index 00000000000000..c7d09eada0eff2
--- /dev/null
+++ b/packages/material-ui/src/Popover/popoverClasses.js
@@ -0,0 +1,9 @@
+import { generateUtilityClass, generateUtilityClasses } from '@material-ui/unstyled';
+
+export function getPopoverUtilityClass(slot) {
+  return generateUtilityClass('MuiPopover', slot);
+}
+
+const popoverClasses = generateUtilityClasses('MuiPopover', ['root', 'paper']);
+
+export default popoverClasses;