diff --git a/types/ramda/index.d.ts b/types/ramda/index.d.ts
index cc9616f131..44ef2167ae 100644
--- a/types/ramda/index.d.ts
+++ b/types/ramda/index.d.ts
@@ -1074,6 +1074,16 @@ declare namespace R {
         /**
          * Like mapObj, but but passes additional arguments to the predicate function.
          */
+        mapObjIndexed<T, TResult>(
+            fn: (value: T, key: string, obj?: {
+                [key: string]: T
+            }) => TResult,
+            obj: {
+                [key: string]: T
+            }
+        ): {
+            [key: string]: TResult
+        };
         mapObjIndexed<T, TResult>(fn: (value: T, key: string, obj?: any) => TResult, obj: any): { [index: string]: TResult };
         mapObjIndexed<T, TResult>(fn: (value: T, key: string, obj?: any) => TResult): (obj: any) => { [index: string]: TResult };
 
diff --git a/types/ramda/ramda-tests.ts b/types/ramda/ramda-tests.ts
index 32bae5fa0c..1b78af72b2 100644
--- a/types/ramda/ramda-tests.ts
+++ b/types/ramda/ramda-tests.ts
@@ -502,6 +502,20 @@ R.times(i, 5);
     R.mapObjIndexed(prependKeyAndDouble, values); // => { x: 'x2', y: 'y4', z: 'z6' }
 });
 
+(() => {
+    const testObject: {
+        [key: string]: Error
+    } = {
+        hello: new Error('hello'),
+    };
+    const errorMessages = R.mapObjIndexed(
+        function test(value, key) {
+            // value should be inferred.
+            return value.message + String(key);
+        }, testObject);
+    console.log(errorMessages);
+});
+
 (() => {
     const a: number[]   = R.ap([R.multiply(2), R.add(3)], [1, 2, 3]); // => [2, 4, 6, 4, 5, 6]
     const b: number[][] = R.of([1]); // => [[1]]