diff --git a/collections/group_by.ts b/collections/group_by.ts
deleted file mode 100644
index 2cbeea6fb2f1..000000000000
--- a/collections/group_by.ts
+++ /dev/null
@@ -1,46 +0,0 @@
-// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
-// This module is browser compatible.
-
-/**
- * Applies the given selector to each element in the given array, returning a
- * Record containing the results as keys and all values that produced that key
- * as values.
- *
- * @example
- * ```ts
- * import { groupBy } from "https://deno.land/std@$STD_VERSION/collections/group_by.ts";
- * import { assertEquals } from "https://deno.land/std@$STD_VERSION/assert/assert_equals.ts";
- *
- * const people = [
- *   { name: "Anna" },
- *   { name: "Arnold" },
- *   { name: "Kim" },
- * ];
- * const peopleByFirstLetter = groupBy(people, (it) => it.name.charAt(0));
- *
- * assertEquals(
- *   peopleByFirstLetter,
- *   {
- *     "A": [{ name: "Anna" }, { name: "Arnold" }],
- *     "K": [{ name: "Kim" }],
- *   },
- * );
- * ```
- *
- * @deprecated (will be removed in 0.211.0) Use {@linkcode Object.groupBy} instead.
- */
-export function groupBy<T, K extends PropertyKey>(
-  iterable: Iterable<T>,
-  selector: (element: T, index: number) => K,
-): Partial<Record<K, T[]>> {
-  const ret: Partial<Record<K, T[]>> = {};
-  let i = 0;
-
-  for (const element of iterable) {
-    const key = selector(element, i++);
-    const arr: T[] = ret[key] ??= [];
-    arr.push(element);
-  }
-
-  return ret;
-}
diff --git a/collections/group_by_test.ts b/collections/group_by_test.ts
deleted file mode 100644
index 62368249f843..000000000000
--- a/collections/group_by_test.ts
+++ /dev/null
@@ -1,136 +0,0 @@
-// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
-
-import { assertEquals } from "../assert/mod.ts";
-import { groupBy } from "./group_by.ts";
-
-function groupByTest<T>(
-  input: [Array<T>, (el: T) => PropertyKey],
-  expected: { [x: string]: Array<T> },
-  message?: string,
-) {
-  const actual = groupBy(...input);
-  assertEquals(actual, expected, message);
-}
-
-Deno.test({
-  name: "groupBy() handles no mutation",
-  fn() {
-    const arrayA = [1.1, 4.2, 4.5];
-    groupBy(arrayA, () => "test");
-
-    assertEquals(arrayA, [1.1, 4.2, 4.5]);
-  },
-});
-
-Deno.test({
-  name: "groupBy() handles empty input",
-  fn() {
-    groupByTest(
-      [[], () => "a"],
-      {},
-    );
-  },
-});
-
-Deno.test({
-  name: "groupBy() handles constant key",
-  fn() {
-    groupByTest(
-      [[1, 3, 5, 6], () => "a"],
-      { a: [1, 3, 5, 6] },
-    );
-  },
-});
-Deno.test({
-  name: "groupBy() handles non-string key",
-  fn() {
-    groupByTest(
-      [
-        [
-          { number: 1, name: "a" },
-          { number: 1, name: "b" },
-          { number: 2, name: "c" },
-          { number: 3, name: "d" },
-        ],
-        ({ number }) => number,
-      ],
-      {
-        1: [{ number: 1, name: "a" }, { number: 1, name: "b" }],
-        2: [{ number: 2, name: "c" }],
-        3: [{ number: 3, name: "d" }],
-      },
-    );
-  },
-});
-
-Deno.test({
-  name: "groupBy() handles empty key",
-  fn() {
-    groupByTest(
-      [
-        ["Foo", "b"],
-        (it) => it.charAt(1),
-      ],
-      {
-        "o": ["Foo"],
-        "": ["b"],
-      },
-    );
-  },
-});
-
-Deno.test({
-  name: "groupBy() handles groups",
-  fn() {
-    groupByTest(
-      [
-        ["Anna", "Marija", "Karl", "Arnold", "Martha"],
-        (it) => it.charAt(0),
-      ],
-      {
-        "A": ["Anna", "Arnold"],
-        "M": ["Marija", "Martha"],
-        "K": ["Karl"],
-      },
-    );
-    groupByTest(
-      [
-        [1.2, 2, 2.3, 6.3, 6.9, 6],
-        (it) => Math.floor(it).toString(),
-      ],
-      {
-        "1": [1.2],
-        "2": [2, 2.3],
-        "6": [6.3, 6.9, 6],
-      },
-    );
-  },
-});
-
-Deno.test({
-  name: "groupBy() handles callback index",
-  fn() {
-    const actual = groupBy(
-      ["a", "b", "c", "d"],
-      (_, i) => i % 2 === 0 ? "even" : "odd",
-    );
-
-    const expected = { even: ["a", "c"], odd: ["b", "d"] };
-
-    assertEquals(actual, expected);
-  },
-});
-
-Deno.test({
-  name: "groupBy() handles iterable input",
-  fn() {
-    function* count(): Generator<number, void> {
-      for (let i = 0; i < 5; i += 1) yield i;
-    }
-
-    const actual = groupBy(count(), (n) => n % 2 === 0 ? "even" : "odd");
-    const expected = { even: [0, 2, 4], odd: [1, 3] };
-
-    assertEquals(actual, expected);
-  },
-});
diff --git a/collections/mod.ts b/collections/mod.ts
index 74afcb183b00..f9dff0b6b3f9 100644
--- a/collections/mod.ts
+++ b/collections/mod.ts
@@ -21,7 +21,6 @@ export * from "./drop_while.ts";
 export * from "./filter_entries.ts";
 export * from "./filter_keys.ts";
 export * from "./filter_values.ts";
-export * from "./group_by.ts";
 export * from "./intersect.ts";
 export * from "./map_entries.ts";
 export * from "./map_keys.ts";