diff --git a/src/index.ts b/src/index.ts
index b1ededfba..777140ee1 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -31,6 +31,7 @@ export * as selector from './utils/selector';
 export * from './utils/address';
 export * from './utils/url';
 export * from './utils/calldata';
+export * from './utils/calldata/enum';
 export * from './utils/contract';
 export * from './utils/events';
 
diff --git a/src/types/cairoEnum.ts b/src/types/cairoEnum.ts
new file mode 100644
index 000000000..7325edb39
--- /dev/null
+++ b/src/types/cairoEnum.ts
@@ -0,0 +1,3 @@
+import { CairoCustomEnum, CairoOption, CairoResult } from '../utils/calldata/enum';
+
+export type CairoEnum = CairoCustomEnum | CairoOption<Object> | CairoResult<Object, Object>;
diff --git a/src/types/contract.ts b/src/types/contract.ts
index 924ec6dcb..914d76e01 100644
--- a/src/types/contract.ts
+++ b/src/types/contract.ts
@@ -1,26 +1,9 @@
+import { CairoEnum } from './cairoEnum';
 import { BigNumberish, BlockIdentifier, RawArgsArray, Signature } from './lib';
 
 export type AsyncContractFunction<T = any> = (...args: ArgsOrCalldataWithOptions) => Promise<T>;
 export type ContractFunction = (...args: ArgsOrCalldataWithOptions) => any;
 
-export interface CairoCustomEnumInterface {
-  [key: string]: any;
-  unwrap: Function;
-}
-export interface CairoOptionInterface {
-  [key: string]: any;
-  unwrap: Function;
-  isSome: Function;
-  isNone: Function;
-}
-export interface CairoResultInterface {
-  [key: string]: any;
-  unwrap: Function;
-  isOK: Function;
-  isErr: Function;
-}
-export type CairoEnum = CairoCustomEnumInterface | CairoOptionInterface | CairoResultInterface;
-
 export type Result =
   | {
       [key: string]: any;
diff --git a/src/types/index.ts b/src/types/index.ts
index ae41cbca2..5c17a17cc 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -7,3 +7,4 @@ export * from './typedData';
 export * from './api/sequencer';
 export * from './api/rpc';
 export * from './calldata';
+export * from './cairoEnum';
diff --git a/src/utils/calldata/enum/CairoCustomEnum.ts b/src/utils/calldata/enum/CairoCustomEnum.ts
new file mode 100644
index 000000000..229e6c287
--- /dev/null
+++ b/src/utils/calldata/enum/CairoCustomEnum.ts
@@ -0,0 +1,43 @@
+export type CairoEnumRaw = {
+  [key: string]: any;
+};
+
+/**
+ * Class to handle Cairo custom Enum
+ * @param enumContent object containing the variants and its content. Example :
+ *  {Success: 234, Warning: undefined, Error: undefined}.
+ *  Only one variant with a value, object, array.
+ * @returns an instance representing a Cairo custom Enum.
+ * @example ```typescript
+ * const myCairoEnum = new CairoCustomEnum( {Success: undefined, Warning: "0x7f32ea", Error: undefined})
+ * ```
+ */
+export class CairoCustomEnum {
+  /**
+   * direct readonly access to variants of the Cairo Custom Enum.
+   * @returns a value of type any
+   * @example ```typescript
+   * const successValue = myCairoEnum.variant.Success;
+   */
+  readonly variant: CairoEnumRaw;
+
+  constructor(enumContent: CairoEnumRaw) {
+    // TODO : add checks of validity of enumContent
+    this.variant = enumContent;
+  }
+
+  /**
+   *
+   * @returns the content of the valid variant of a Cairo custom Enum.
+   */
+  public unwrap(): any {
+    const variants = Object.entries(this.variant);
+    const activeVariant = variants.find((item) => typeof item[1] !== 'undefined');
+    if (typeof activeVariant === 'undefined') {
+      return undefined;
+    }
+    return activeVariant[1];
+  }
+
+  // TODO : add function 'activeVariant' -> string
+}
diff --git a/src/utils/calldata/enum/CairoOption.ts b/src/utils/calldata/enum/CairoOption.ts
new file mode 100644
index 000000000..d88cd513f
--- /dev/null
+++ b/src/utils/calldata/enum/CairoOption.ts
@@ -0,0 +1,59 @@
+export enum CairoOptionVariant {
+  Some = 0,
+  None = 1,
+}
+
+/**
+ * Class to handle Cairo Option
+ * @param variant CairoOptionVariant.Some or CairoOptionVariant.None
+ * @param someContent value of type T.
+ * @returns an instance representing a Cairo Option.
+ * @example ```typescript
+ * const myOption = new CairoOption<BigNumberish>(CairoOptionVariant.Some, "0x54dda8");
+ * ```
+ */
+export class CairoOption<T> {
+  readonly Some?: T;
+
+  readonly None?: boolean;
+
+  constructor(variant: CairoOptionVariant, someContent?: T) {
+    if (variant === CairoOptionVariant.Some) {
+      if (typeof someContent === 'undefined') {
+        throw new Error(
+          'The creation of a Cairo Option with "Some" variant needs a content as input.'
+        );
+      }
+      this.Some = someContent;
+    }
+    this.None = true;
+  }
+
+  /**
+   *
+   * @returns the content of the valid variant of a Cairo custom Enum.
+   *  If None, returns 'undefined'.
+   */
+  public unwrap(): T | undefined {
+    if (this.None) {
+      return undefined;
+    }
+    return this.Some;
+  }
+
+  /**
+   *
+   * @returns true if the valid variant is 'isSome'.
+   */
+  public isSome(): boolean {
+    return !(typeof this.Some === 'undefined');
+  }
+
+  /**
+   *
+   * @returns true if the valid variant is 'isNone'.
+   */
+  public isNone(): boolean {
+    return this.None === true;
+  }
+}
diff --git a/src/utils/calldata/enum/CairoResult.ts b/src/utils/calldata/enum/CairoResult.ts
new file mode 100644
index 000000000..bf806453a
--- /dev/null
+++ b/src/utils/calldata/enum/CairoResult.ts
@@ -0,0 +1,56 @@
+export enum CairoResultVariant {
+  Ok = 0,
+  Err = 1,
+}
+
+/**
+ * Class to handle Cairo Result
+ * @param variant CairoResultVariant.Ok or CairoResultVariant.Err
+ * @param resultContent value of type T or U.
+ * @returns an instance representing a Cairo Result.
+ * @example ```typescript
+ * const myOption = new CairoResult<BigNumberish,CustomError>(CairoResultVariant.Ok, "0x54dda8");
+ * ```
+ */
+export class CairoResult<T, U> {
+  readonly Ok?: T;
+
+  readonly Err?: U;
+
+  constructor(variant: CairoResultVariant, resultContent: T | U) {
+    if (variant === CairoResultVariant.Ok) {
+      this.Ok = resultContent as T;
+    }
+    this.Err = resultContent as U;
+  }
+
+  /**
+   *
+   * @returns the content of the valid variant of a Cairo Result.
+   */
+  public unwrap(): T | U {
+    if (typeof this.Ok !== 'undefined') {
+      return this.Ok;
+    }
+    if (typeof this.Err !== 'undefined') {
+      return this.Err;
+    }
+    throw new Error('Both Result.Ok and .Err are undefined. Not authorized.');
+  }
+
+  /**
+   *
+   * @returns true if the valid variant is 'Ok'.
+   */
+  public isOk(): boolean {
+    return !(typeof this.Ok === 'undefined');
+  }
+
+  /**
+   *
+   * @returns true if the valid variant is 'isErr'.
+   */
+  public isErr(): boolean {
+    return !(typeof this.Err === 'undefined');
+  }
+}
diff --git a/src/utils/calldata/enum/index.ts b/src/utils/calldata/enum/index.ts
new file mode 100644
index 000000000..a9132c871
--- /dev/null
+++ b/src/utils/calldata/enum/index.ts
@@ -0,0 +1,3 @@
+export * from './CairoCustomEnum';
+export * from './CairoOption';
+export * from './CairoResult';
diff --git a/src/utils/calldata/responseParser.ts b/src/utils/calldata/responseParser.ts
index 9d0ffbb19..02dbc2a13 100644
--- a/src/utils/calldata/responseParser.ts
+++ b/src/utils/calldata/responseParser.ts
@@ -5,7 +5,7 @@ import {
   AbiStructs,
   Args,
   BigNumberish,
-  CairoCustomEnum,
+  CairoEnum,
   ParsedStruct,
 } from '../../types';
 import { uint256ToBN } from '../uint256';
@@ -19,6 +19,7 @@ import {
   isTypeTuple,
   isTypeUint256,
 } from './cairo';
+import { CairoCustomEnum, CairoEnumRaw } from './enum';
 import extractTupleMemberTypes from './tuple';
 
 /**
@@ -56,7 +57,7 @@ function parseResponseValue(
   element: { name: string; type: string },
   structs: AbiStructs,
   enums: AbiEnums
-): BigNumberish | ParsedStruct | boolean | any[] {
+): BigNumberish | ParsedStruct | boolean | any[] | CairoEnum {
   // type uint256 struct (c1v2)
   if (isTypeUint256(element.type)) {
     const low = responseIterator.next().value;
@@ -72,9 +73,25 @@ function parseResponseValue(
     }, {} as any);
   }
 
-  // type Enum
-  // if (element.type in enums && enums[element.type]) {
-  // }
+  // type Enum (only CustomEnum)
+  if (element.type in enums && enums[element.type]) {
+    const variantNum: number = Number(responseIterator.next().value); // get variant number
+    const rawEnum = enums[element.type].variants.reduce((acc, variant, num) => {
+      if (num === variantNum) {
+        acc[variant.name] = parseResponseValue(
+          responseIterator,
+          { name: '', type: variant.type },
+          structs,
+          enums
+        );
+        return acc;
+      }
+      acc[variant.name] = undefined;
+      return acc;
+    }, {} as CairoEnumRaw);
+    const customEnum = new CairoCustomEnum(rawEnum);
+    return customEnum;
+  }
 
   // type tuple
   if (isTypeTuple(element.type)) {
@@ -91,7 +108,7 @@ function parseResponseValue(
   // type c1 array
   if (isTypeArray(element.type)) {
     // eslint-disable-next-line no-case-declarations
-    const parsedDataArr: (BigNumberish | ParsedStruct | boolean | any[])[] = [];
+    const parsedDataArr: (BigNumberish | ParsedStruct | boolean | any[] | CairoEnum)[] = [];
     const el = { name: '', type: getArrayType(element.type) };
     const len = BigInt(responseIterator.next().value); // get length
     while (parsedDataArr.length < len) {
@@ -132,22 +149,7 @@ export default function responseParser(
       return parseResponseValue(responseIterator, output, structs, enums);
 
     case isTypeEnum(type, enums):
-      const variantNum: number = Number(responseIterator.next().value); // get variant number
-      const myEnum = enums[output.type].variants.reduce((acc, variant, num) => {
-        if (num === variantNum) {
-          acc[variant.name] = parseResponseValue(
-            responseIterator,
-            { name: '0', type: variant.type },
-            structs,
-            enums
-          );
-          return acc;
-        }
-        acc[variant.name] = undefined;
-        return acc;
-      }, {} as Record<string, any>);
-      const customEnum: CairoCustomEnum = { ...myEnum, ...unw };
-      return customEnum;
+      return parseResponseValue(responseIterator, output, structs, enums);
 
     case isTypeArray(type):
       // C1 Array
@@ -156,7 +158,7 @@ export default function responseParser(
       }
       // C0 Array
       // eslint-disable-next-line no-case-declarations
-      const parsedDataArr: (BigNumberish | ParsedStruct | boolean | any[])[] = [];
+      const parsedDataArr: (BigNumberish | ParsedStruct | boolean | any[] | CairoEnum)[] = [];
       if (parsedResult && parsedResult[`${name}_len`]) {
         const arrLen = parsedResult[`${name}_len`] as number;
         while (parsedDataArr.length < arrLen) {