diff --git a/src/material/expansion/expansion-panel-base.ts b/src/material/expansion/expansion-panel-base.ts
new file mode 100644
index 000000000000..2b64a08d0465
--- /dev/null
+++ b/src/material/expansion/expansion-panel-base.ts
@@ -0,0 +1,25 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {InjectionToken} from '@angular/core';
+import {CdkAccordionItem} from '@angular/cdk/accordion';
+
+/**
+ * Base interface for a `MatExpansionPanel`.
+ * @docs-private
+ */
+export interface MatExpansionPanelBase extends CdkAccordionItem {
+  /** Whether the toggle indicator should be hidden. */
+  hideToggle: boolean;
+}
+
+/**
+ * Token used to provide a `MatExpansionPanel` to `MatExpansionPanelContent`.
+ * Used to avoid circular imports between `MatExpansionPanel` and `MatExpansionPanelContent`.
+ */
+export const MAT_EXPANSION_PANEL = new InjectionToken<MatExpansionPanelBase>('MAT_EXPANSION_PANEL');
diff --git a/src/material/expansion/expansion-panel-content.ts b/src/material/expansion/expansion-panel-content.ts
index b755fc8870f1..18e29a116bed 100644
--- a/src/material/expansion/expansion-panel-content.ts
+++ b/src/material/expansion/expansion-panel-content.ts
@@ -6,7 +6,8 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {Directive, TemplateRef} from '@angular/core';
+import {Directive, TemplateRef, Inject, Optional} from '@angular/core';
+import {MAT_EXPANSION_PANEL, MatExpansionPanelBase} from './expansion-panel-base';
 
 /**
  * Expansion panel content that will be rendered lazily
@@ -16,5 +17,7 @@ import {Directive, TemplateRef} from '@angular/core';
   selector: 'ng-template[matExpansionPanelContent]'
 })
 export class MatExpansionPanelContent {
-  constructor(public _template: TemplateRef<any>) {}
+  constructor(
+    public _template: TemplateRef<any>,
+    @Inject(MAT_EXPANSION_PANEL) @Optional() public _expansionPanel?: MatExpansionPanelBase) {}
 }
diff --git a/src/material/expansion/expansion-panel.ts b/src/material/expansion/expansion-panel.ts
index b26f0a6f26ff..29f67aa1ee83 100644
--- a/src/material/expansion/expansion-panel.ts
+++ b/src/material/expansion/expansion-panel.ts
@@ -40,6 +40,7 @@ import {filter, startWith, take, distinctUntilChanged} from 'rxjs/operators';
 import {matExpansionAnimations} from './expansion-animations';
 import {MatExpansionPanelContent} from './expansion-panel-content';
 import {MAT_ACCORDION, MatAccordionBase, MatAccordionTogglePosition} from './accordion-base';
+import {MAT_EXPANSION_PANEL} from './expansion-panel-base';
 
 /** MatExpansionPanel's states. */
 export type MatExpansionPanelState = 'expanded' | 'collapsed';
@@ -90,6 +91,7 @@ export const MAT_EXPANSION_PANEL_DEFAULT_OPTIONS =
     // Provide MatAccordion as undefined to prevent nested expansion panels from registering
     // to the same accordion.
     {provide: MAT_ACCORDION, useValue: undefined},
+    {provide: MAT_EXPANSION_PANEL, useExisting: MatExpansionPanel}
   ],
   host: {
     'class': 'mat-expansion-panel',
@@ -197,7 +199,7 @@ export class MatExpansionPanel extends CdkAccordionItem implements AfterContentI
   }
 
   ngAfterContentInit() {
-    if (this._lazyContent) {
+    if (this._lazyContent && this._lazyContent._expansionPanel === this) {
       // Render the content as soon as the panel becomes open.
       this.opened.pipe(
         startWith(null!),
diff --git a/src/material/expansion/expansion.spec.ts b/src/material/expansion/expansion.spec.ts
index 7b0dbd34a58b..d3dd5862e9f2 100644
--- a/src/material/expansion/expansion.spec.ts
+++ b/src/material/expansion/expansion.spec.ts
@@ -25,6 +25,7 @@ describe('MatExpansionPanel', () => {
         PanelWithCustomMargin,
         LazyPanelWithContent,
         LazyPanelOpenOnLoad,
+        NestedLazyPanelWithContent,
         PanelWithTwoWayBinding,
       ],
     });
@@ -70,6 +71,28 @@ describe('MatExpansionPanel', () => {
         .toContain('Some content', 'Expected content to be rendered.');
   }));
 
+  it('should not render lazy content from a child panel inside the parent', fakeAsync(() => {
+    const fixture = TestBed.createComponent(NestedLazyPanelWithContent);
+    fixture.componentInstance.parentExpanded = true;
+    fixture.detectChanges();
+
+    const parentContent: HTMLElement =
+        fixture.nativeElement.querySelector('.parent-panel .mat-expansion-panel-content');
+    const childContent: HTMLElement =
+        fixture.nativeElement.querySelector('.child-panel .mat-expansion-panel-content');
+
+    expect(parentContent.textContent!.trim())
+        .toBe('Parent content', 'Expected only parent content to be rendered.');
+    expect(childContent.textContent!.trim())
+        .toBe('', 'Expected child content element to be empty.');
+
+    fixture.componentInstance.childExpanded = true;
+    fixture.detectChanges();
+
+    expect(childContent.textContent!.trim())
+        .toBe('Child content', 'Expected child content element to be rendered.');
+  }));
+
   it('emit correct events for change in panel expanded state', () => {
     const fixture = TestBed.createComponent(PanelWithContent);
     fixture.componentInstance.expanded = true;
@@ -490,3 +513,21 @@ class LazyPanelOpenOnLoad {}
 class PanelWithTwoWayBinding {
   expanded = false;
 }
+
+
+@Component({
+  template: `
+    <mat-expansion-panel class="parent-panel" [expanded]="parentExpanded">
+      Parent content
+
+      <mat-expansion-panel class="child-panel" [expanded]="childExpanded">
+        <ng-template matExpansionPanelContent>Child content</ng-template>
+      </mat-expansion-panel>
+    </mat-expansion-panel>
+  `
+})
+class NestedLazyPanelWithContent {
+  parentExpanded = false;
+  childExpanded = false;
+}
+
diff --git a/tools/public_api_guard/material/expansion.d.ts b/tools/public_api_guard/material/expansion.d.ts
index 431271a94520..e43c873c6c74 100644
--- a/tools/public_api_guard/material/expansion.d.ts
+++ b/tools/public_api_guard/material/expansion.d.ts
@@ -61,8 +61,9 @@ export declare class MatExpansionPanelActionRow {
 }
 
 export declare class MatExpansionPanelContent {
+    _expansionPanel?: MatExpansionPanelBase | undefined;
     _template: TemplateRef<any>;
-    constructor(_template: TemplateRef<any>);
+    constructor(_template: TemplateRef<any>, _expansionPanel?: MatExpansionPanelBase | undefined);
 }
 
 export interface MatExpansionPanelDefaultOptions {