diff --git a/types/node/index.d.ts b/types/node/index.d.ts
index 2296d085b9..73558e4a8f 100644
--- a/types/node/index.d.ts
+++ b/types/node/index.d.ts
@@ -207,20 +207,20 @@ declare var console: Console;
 declare var __filename: string;
 declare var __dirname: string;
 
-declare function setTimeout(callback: (...args: any[]) => void, ms: number, ...args: any[]): NodeJS.Timer;
+declare function setTimeout(callback: (...args: any[]) => void, ms: number, ...args: any[]): NodeJS.Timeout;
 declare namespace setTimeout {
     function __promisify__(ms: number): Promise<void>;
     function __promisify__<T>(ms: number, value: T): Promise<T>;
 }
-declare function clearTimeout(timeoutId: NodeJS.Timer): void;
-declare function setInterval(callback: (...args: any[]) => void, ms: number, ...args: any[]): NodeJS.Timer;
-declare function clearInterval(intervalId: NodeJS.Timer): void;
-declare function setImmediate(callback: (...args: any[]) => void, ...args: any[]): any;
+declare function clearTimeout(timeoutId: NodeJS.Timeout): void;
+declare function setInterval(callback: (...args: any[]) => void, ms: number, ...args: any[]): NodeJS.Timeout;
+declare function clearInterval(intervalId: NodeJS.Timeout): void;
+declare function setImmediate(callback: (...args: any[]) => void, ...args: any[]): NodeJS.Immediate;
 declare namespace setImmediate {
     function __promisify__(): Promise<void>;
     function __promisify__<T>(value: T): Promise<T>;
 }
-declare function clearImmediate(immediateId: any): void;
+declare function clearImmediate(immediateId: NodeJS.Immediate): void;
 
 // TODO: change to `type NodeRequireFunction = (id: string) => any;` in next mayor version.
 interface NodeRequireFunction {
@@ -959,9 +959,9 @@ declare namespace NodeJS {
         Uint8ClampedArray: Function;
         WeakMap: WeakMapConstructor;
         WeakSet: WeakSetConstructor;
-        clearImmediate: (immediateId: any) => void;
-        clearInterval: (intervalId: Timer) => void;
-        clearTimeout: (timeoutId: Timer) => void;
+        clearImmediate: (immediateId: Immediate) => void;
+        clearInterval: (intervalId: Timeout) => void;
+        clearTimeout: (timeoutId: Timeout) => void;
         console: typeof console;
         decodeURI: typeof decodeURI;
         decodeURIComponent: typeof decodeURIComponent;
@@ -976,9 +976,9 @@ declare namespace NodeJS {
         parseInt: typeof parseInt;
         process: Process;
         root: Global;
-        setImmediate: (callback: (...args: any[]) => void, ...args: any[]) => any;
-        setInterval: (callback: (...args: any[]) => void, ms: number, ...args: any[]) => Timer;
-        setTimeout: (callback: (...args: any[]) => void, ms: number, ...args: any[]) => Timer;
+        setImmediate: (callback: (...args: any[]) => void, ...args: any[]) => Immediate;
+        setInterval: (callback: (...args: any[]) => void, ms: number, ...args: any[]) => Timeout;
+        setTimeout: (callback: (...args: any[]) => void, ms: number, ...args: any[]) => Timeout;
         undefined: typeof undefined;
         unescape: (str: string) => string;
         gc: () => void;
@@ -987,6 +987,19 @@ declare namespace NodeJS {
 
     interface Timer {
         ref(): void;
+        refresh(): void;
+        unref(): void;
+    }
+
+    class Immediate {
+        ref(): void;
+        unref(): void;
+        _onImmediate: Function; // to distinguish it from the Timeout class
+    }
+
+    class Timeout implements Timer {
+        ref(): void;
+        refresh(): void;
         unref(): void;
     }
 
@@ -7211,20 +7224,20 @@ declare module "v8" {
 }
 
 declare module "timers" {
-    function setTimeout(callback: (...args: any[]) => void, ms: number, ...args: any[]): NodeJS.Timer;
+    function setTimeout(callback: (...args: any[]) => void, ms: number, ...args: any[]): NodeJS.Timeout;
     namespace setTimeout {
         function __promisify__(ms: number): Promise<void>;
         function __promisify__<T>(ms: number, value: T): Promise<T>;
     }
-    function clearTimeout(timeoutId: NodeJS.Timer): void;
-    function setInterval(callback: (...args: any[]) => void, ms: number, ...args: any[]): NodeJS.Timer;
-    function clearInterval(intervalId: NodeJS.Timer): void;
-    function setImmediate(callback: (...args: any[]) => void, ...args: any[]): any;
+    function clearTimeout(timeoutId: NodeJS.Timeout): void;
+    function setInterval(callback: (...args: any[]) => void, ms: number, ...args: any[]): NodeJS.Timeout;
+    function clearInterval(intervalId: NodeJS.Timeout): void;
+    function setImmediate(callback: (...args: any[]) => void, ...args: any[]): NodeJS.Immediate;
     namespace setImmediate {
         function __promisify__(): Promise<void>;
         function __promisify__<T>(value: T): Promise<T>;
     }
-    function clearImmediate(immediateId: any): void;
+    function clearImmediate(immediateId: NodeJS.Immediate): void;
 }
 
 declare module "console" {