diff --git a/Userland/Libraries/LibJS/Runtime/CommonPropertyNames.h b/Userland/Libraries/LibJS/Runtime/CommonPropertyNames.h
index 4ad8139274..6b4ddd987b 100644
--- a/Userland/Libraries/LibJS/Runtime/CommonPropertyNames.h
+++ b/Userland/Libraries/LibJS/Runtime/CommonPropertyNames.h
@@ -215,6 +215,7 @@ namespace JS {
     P(round)                                 \
     P(seal)                                  \
     P(set)                                   \
+    P(setDate)                               \
     P(setFullYear)                           \
     P(setHours)                              \
     P(setMilliseconds)                       \
diff --git a/Userland/Libraries/LibJS/Runtime/DatePrototype.cpp b/Userland/Libraries/LibJS/Runtime/DatePrototype.cpp
index 75d7771a7c..4f0c958b18 100644
--- a/Userland/Libraries/LibJS/Runtime/DatePrototype.cpp
+++ b/Userland/Libraries/LibJS/Runtime/DatePrototype.cpp
@@ -39,6 +39,7 @@ void DatePrototype::initialize(GlobalObject& global_object)
     Object::initialize(global_object);
     u8 attr = Attribute::Writable | Attribute::Configurable;
     define_native_function(vm.names.getDate, get_date, 0, attr);
+    define_native_function(vm.names.setDate, set_date, 1, attr);
     define_native_function(vm.names.getDay, get_day, 0, attr);
     define_native_function(vm.names.getFullYear, get_full_year, 0, attr);
     define_native_function(vm.names.setFullYear, set_full_year, 3, attr);
@@ -102,6 +103,29 @@ JS_DEFINE_NATIVE_FUNCTION(DatePrototype::get_date)
     return Value(this_object->date());
 }
 
+JS_DEFINE_NATIVE_FUNCTION(DatePrototype::set_date)
+{
+    auto* this_object = typed_this(vm, global_object);
+    if (!this_object)
+        return {};
+
+    auto& datetime = this_object->datetime();
+
+    auto new_date_value = vm.argument(0).to_number(global_object);
+    if (vm.exception())
+        return {};
+    if (!new_date_value.is_finite_number()) {
+        this_object->set_is_invalid(true);
+        return js_nan();
+    }
+    auto new_date = new_date_value.as_i32();
+
+    this_object->set_is_invalid(false);
+
+    datetime.set_time(datetime.year(), datetime.month(), new_date, datetime.hour(), datetime.minute(), datetime.second());
+    return Value(this_object->time());
+}
+
 JS_DEFINE_NATIVE_FUNCTION(DatePrototype::get_day)
 {
     auto* this_object = typed_this(vm, global_object);
diff --git a/Userland/Libraries/LibJS/Runtime/DatePrototype.h b/Userland/Libraries/LibJS/Runtime/DatePrototype.h
index a4241ce1a6..496d90907a 100644
--- a/Userland/Libraries/LibJS/Runtime/DatePrototype.h
+++ b/Userland/Libraries/LibJS/Runtime/DatePrototype.h
@@ -20,6 +20,7 @@ public:
 
 private:
     JS_DECLARE_NATIVE_FUNCTION(get_date);
+    JS_DECLARE_NATIVE_FUNCTION(set_date);
     JS_DECLARE_NATIVE_FUNCTION(get_day);
     JS_DECLARE_NATIVE_FUNCTION(get_full_year);
     JS_DECLARE_NATIVE_FUNCTION(set_full_year);
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Date/Date.prototype.setDate.js b/Userland/Libraries/LibJS/Tests/builtins/Date/Date.prototype.setDate.js
new file mode 100644
index 0000000000..b8cd57710f
--- /dev/null
+++ b/Userland/Libraries/LibJS/Tests/builtins/Date/Date.prototype.setDate.js
@@ -0,0 +1,47 @@
+test("no arguments", () => {
+    let date = new Date(2021, 0, 1);
+    date.setDate();
+    expect(date.getTime()).toBe(NaN);
+});
+
+test("NaN or undefined as only argument", () => {
+    let date = new Date(2021, 0, 1);
+    date.setDate(NaN);
+    expect(date.getTime()).toBe(NaN);
+
+    date = new Date(2021, 0, 1);
+    date.setDate(undefined);
+    expect(date.getTime()).toBe(NaN);
+
+    date = new Date(2021, 0, 1);
+    date.setDate("a");
+    expect(date.getTime()).toBe(NaN);
+});
+
+test("Day as argument", () => {
+    let date = new Date(2021, 0, 1);
+
+    date.setDate(17);
+    expect(date.getDate()).toBe(17);
+    expect(date.getMonth()).toBe(0);
+    expect(date.getFullYear()).toBe(2021);
+    expect(date.getHours()).toBe(0);
+    expect(date.getMinutes()).toBe(0);
+    expect(date.getSeconds()).toBe(0);
+    expect(date.getMilliseconds()).toBe(0);
+});
+
+test("Make Invalid Date valid again", () => {
+    let date = new Date(2021, 0, 1);
+    date.setDate(NaN);
+    expect(date.getTime()).toBe(NaN);
+
+    date.setDate(16);
+    expect(date.getFullYear()).toBe(2021);
+    expect(date.getMonth()).toBe(0);
+    expect(date.getDate()).toBe(16);
+    expect(date.getHours()).toBe(0);
+    expect(date.getMinutes()).toBe(0);
+    expect(date.getSeconds()).toBe(0);
+    expect(date.getMilliseconds()).toBe(0);
+});