diff --git a/cli/js/lib.deno.ns.d.ts b/cli/js/lib.deno.ns.d.ts
index 3242ee2807e9cf..ec4e0a06a71356 100644
--- a/cli/js/lib.deno.ns.d.ts
+++ b/cli/js/lib.deno.ns.d.ts
@@ -1043,13 +1043,6 @@ declare namespace Deno {
    * Requires `allow-write` permission. */
   export function mkdirSync(path: string, options?: MkdirOptions): void;
 
-  /** @deprecated */
-  export function mkdirSync(
-    path: string,
-    recursive?: boolean,
-    mode?: number
-  ): void;
-
   /** Creates a new directory with the specified path.
    *
    *       await Deno.mkdir("new_dir");
@@ -1061,13 +1054,6 @@ declare namespace Deno {
    * Requires `allow-write` permission. */
   export function mkdir(path: string, options?: MkdirOptions): Promise<void>;
 
-  /** @deprecated */
-  export function mkdir(
-    path: string,
-    recursive?: boolean,
-    mode?: number
-  ): Promise<void>;
-
   export interface MakeTempOptions {
     /** Directory where the temporary directory should be created (defaults to
      * the env variable TMPDIR, or the system's default, usually /tmp). */
diff --git a/cli/js/ops/fs/mkdir.ts b/cli/js/ops/fs/mkdir.ts
index 8ecc516761e98f..374a00d835fa71 100644
--- a/cli/js/ops/fs/mkdir.ts
+++ b/cli/js/ops/fs/mkdir.ts
@@ -3,25 +3,14 @@ import { sendSync, sendAsync } from "../dispatch_json.ts";
 
 type MkdirArgs = { path: string; recursive: boolean; mode?: number };
 
-// TODO(ry) The complexity in argument parsing is to support deprecated forms of
-// mkdir and mkdirSync.
-function mkdirArgs(
-  path: string,
-  optionsOrRecursive?: MkdirOptions | boolean,
-  mode?: number
-): MkdirArgs {
+function mkdirArgs(path: string, options?: MkdirOptions): MkdirArgs {
   const args: MkdirArgs = { path, recursive: false };
-  if (typeof optionsOrRecursive == "boolean") {
-    args.recursive = optionsOrRecursive;
-    if (mode) {
-      args.mode = mode;
-    }
-  } else if (optionsOrRecursive) {
-    if (typeof optionsOrRecursive.recursive == "boolean") {
-      args.recursive = optionsOrRecursive.recursive;
+  if (options) {
+    if (typeof options.recursive == "boolean") {
+      args.recursive = options.recursive;
     }
-    if (optionsOrRecursive.mode) {
-      args.mode = optionsOrRecursive.mode;
+    if (options.mode) {
+      args.mode = options.mode;
     }
   }
   return args;
@@ -32,18 +21,13 @@ export interface MkdirOptions {
   mode?: number;
 }
 
-export function mkdirSync(
-  path: string,
-  optionsOrRecursive?: MkdirOptions | boolean,
-  mode?: number
-): void {
-  sendSync("op_mkdir", mkdirArgs(path, optionsOrRecursive, mode));
+export function mkdirSync(path: string, options?: MkdirOptions): void {
+  sendSync("op_mkdir", mkdirArgs(path, options));
 }
 
 export async function mkdir(
   path: string,
-  optionsOrRecursive?: MkdirOptions | boolean,
-  mode?: number
+  options?: MkdirOptions
 ): Promise<void> {
-  await sendAsync("op_mkdir", mkdirArgs(path, optionsOrRecursive, mode));
+  await sendAsync("op_mkdir", mkdirArgs(path, options));
 }