diff --git a/Sora/Configuration.swift b/Sora/Configuration.swift
index 72e8c426..6bbd6ea2 100644
--- a/Sora/Configuration.swift
+++ b/Sora/Configuration.swift
@@ -142,6 +142,9 @@ public struct Configuration {
     /// ロールが `.sendrecv` または `.recvonly` のときのみ有効です。
     public var simulcastRid: SimulcastRid?
 
+    /// サイマルキャストマルチコーデックの可否。`true` であればサイマルキャストマルチコーデックを有効にします。
+    public var simulcastMulticodecEnabled: Bool? = nil
+
     /// スポットライトの可否
     /// 詳しくは Sora のスポットライト機能を参照してください。
     public var spotlightEnabled: Spotlight = .disabled
diff --git a/Sora/PeerChannel.swift b/Sora/PeerChannel.swift
index 1dc471fc..763f4eb5 100644
--- a/Sora/PeerChannel.swift
+++ b/Sora/PeerChannel.swift
@@ -331,6 +331,7 @@ class PeerChannel: NSObject, RTCPeerConnectionDelegate {
             spotlightUnfocusRid: configuration.spotlightUnfocusRid,
             simulcastEnabled: simulcast,
             simulcastRid: configuration.simulcastRid,
+            simulcastMulticodecEnabled: configuration.simulcastMulticodecEnabled,
             soraClient: soraClient,
             webRTCVersion: webRTCVersion,
             environment: DeviceInfo.current.description,
diff --git a/Sora/Signaling.swift b/Sora/Signaling.swift
index 674c8775..da63f1ac 100644
--- a/Sora/Signaling.swift
+++ b/Sora/Signaling.swift
@@ -308,6 +308,9 @@ public struct SignalingConnect {
     /// サイマルキャストでの映像の種類
     public var simulcastRid: SimulcastRid?
 
+    /// サイマルキャストマルチコーデックの可否
+    public var simulcastMulticodecEnabled: Bool?
+
     /// :nodoc:
     public var soraClient: String?
 
@@ -770,6 +773,7 @@ extension SignalingConnect: Codable {
         case spotlight_unfocus_rid
         case simulcast
         case simulcast_rid
+        case simulcast_multicodec
         case video
         case audio
         case sora_client
@@ -874,6 +878,8 @@ extension SignalingConnect: Codable {
             }
         }
 
+        try container.encodeIfPresent(simulcastMulticodecEnabled, forKey: .simulcast_multicodec)
+
         switch spotlightEnabled {
         case .enabled:
             try container.encode(true, forKey: .spotlight)