diff --git a/jest/jest.d.ts b/jest/jest.d.ts
index fde9d894f..a5f2c7ef2 100644
--- a/jest/jest.d.ts
+++ b/jest/jest.d.ts
@@ -54,7 +54,7 @@ declare module jest {
         toContain(expected: string): boolean;
         toBeCloseTo(expected: number, delta: number): boolean;
         toBeGreaterThan(expected: number): boolean;
-        toBeLessThen(expected: number): boolean;
+        toBeLessThan(expected: number): boolean;
         toBeCalled(): boolean;
         toBeCalledWith(...args: any[]): boolean;
         lastCalledWith(...args: any[]): boolean;