diff --git a/osu.Game.Tests/Online/TestAPIModMessagePackSerialization.cs b/osu.Game.Tests/Online/TestAPIModMessagePackSerialization.cs
index 4294f89397..74db477cfc 100644
--- a/osu.Game.Tests/Online/TestAPIModMessagePackSerialization.cs
+++ b/osu.Game.Tests/Online/TestAPIModMessagePackSerialization.cs
@@ -68,6 +68,16 @@ public void TestDeserialiseTimeRampMod()
             Assert.That(converted.FinalRate.Value, Is.EqualTo(0.25));
         }
 
+        [Test]
+        public void TestDeserialiseEnumMod()
+        {
+            var apiMod = new APIMod(new TestModEnum { TestSetting = { Value = TestEnum.Value2 } });
+
+            var deserialized = MessagePackSerializer.Deserialize<APIMod>(MessagePackSerializer.Serialize(apiMod));
+
+            Assert.That(deserialized.Settings, Contains.Key("test_setting").With.ContainValue(1));
+        }
+
         private class TestRuleset : Ruleset
         {
             public override IEnumerable<Mod> GetModsFor(ModType type) => new Mod[]
@@ -135,5 +145,22 @@ private class TestModTimeRamp : ModTimeRamp
                 Value = true
             };
         }
+
+        private class TestModEnum : Mod
+        {
+            public override string Name => "Test Mod";
+            public override string Acronym => "TM";
+            public override double ScoreMultiplier => 1;
+
+            [SettingSource("Test")]
+            public Bindable<TestEnum> TestSetting { get; } = new Bindable<TestEnum>();
+        }
+
+        private enum TestEnum
+        {
+            Value1 = 0,
+            Value2 = 1,
+            Value3 = 2
+        }
     }
 }
diff --git a/osu.Game/Online/API/ModSettingsDictionaryFormatter.cs b/osu.Game/Online/API/ModSettingsDictionaryFormatter.cs
index 99e87677fa..dd854acc32 100644
--- a/osu.Game/Online/API/ModSettingsDictionaryFormatter.cs
+++ b/osu.Game/Online/API/ModSettingsDictionaryFormatter.cs
@@ -3,6 +3,7 @@
 
 using System.Buffers;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Text;
 using MessagePack;
 using MessagePack.Formatters;
@@ -41,6 +42,13 @@ public void Serialize(ref MessagePackWriter writer, Dictionary<string, object> v
                         primitiveFormatter.Serialize(ref writer, b.Value, options);
                         break;
 
+                    case IBindable u:
+                        // A mod with unknown (e.g. enum) generic type.
+                        var valueMethod = u.GetType().GetProperty(nameof(IBindable<int>.Value));
+                        Debug.Assert(valueMethod != null);
+                        primitiveFormatter.Serialize(ref writer, valueMethod.GetValue(u), options);
+                        break;
+
                     default:
                         // fall back for non-bindable cases.
                         primitiveFormatter.Serialize(ref writer, kvp.Value, options);