diff --git a/app/api/rooms/[code]/route.ts b/app/api/rooms/[code]/route.ts
index 0ba021f..e0d5203 100644
--- a/app/api/rooms/[code]/route.ts
+++ b/app/api/rooms/[code]/route.ts
@@ -127,7 +127,7 @@ export async function PATCH(
     article?: string;
     startArticle?: string;
     targetArticle?: string;
-    value?: boolean;
+    value?: boolean | number | string;
   };
 
   // Nettoyer les joueurs inactifs uniquement hors partie (lobby/résultats)
@@ -351,6 +351,19 @@ export async function PATCH(
       return Response.json({ room });
     }
 
+    // Hôte change le mode de jeu
+    case "setGameMode": {
+      const host = room.players.find((p) => p.id === playerId);
+      if (!host?.isHost) {
+        return Response.json({ error: "Seul l'hôte peut modifier ce paramètre" }, { status: 403 });
+      }
+      if (value === "race" || value === "all_finish") {
+        room.gameMode = value;
+        await saveRoom(room);
+      }
+      return Response.json({ room });
+    }
+
     // Hôte change la limite de temps
     case "setTimeLimit": {
       const host = room.players.find((p) => p.id === playerId);
diff --git a/app/components/LobbyScreen.tsx b/app/components/LobbyScreen.tsx
index 1407461..54de24f 100644
--- a/app/components/LobbyScreen.tsx
+++ b/app/components/LobbyScreen.tsx
@@ -18,6 +18,7 @@ type LobbyScreenProps = {
   setTotalRounds: (v: number) => void;
   gameMode: Room["gameMode"];
   setGameMode: (v: Room["gameMode"]) => void;
+  onSetGameMode: (v: Room["gameMode"]) => void;
   onSetSearchAllowed: (v: boolean) => void;
   onSetTimeLimit: (v: number) => void;
 };
@@ -37,6 +38,7 @@ export function LobbyScreen({
   setTotalRounds,
   gameMode,
   setGameMode,
+  onSetGameMode,
   onSetSearchAllowed,
   onSetTimeLimit,
 }: LobbyScreenProps) {
@@ -151,7 +153,7 @@ export function LobbyScreen({
             <span className="text-xs text-[#888]">Mode de jeu</span>
             <select
               value={gameMode}
-              onChange={(e) => setGameMode(e.target.value as Room["gameMode"])}
+              onChange={(e) => { const v = e.target.value as Room["gameMode"]; setGameMode(v); onSetGameMode(v); }}
               className="w-full min-h-11 px-2 bg-[#0f0f0f] border border-[#2e2e2e] rounded-xl text-sm text-[#f0f0f0] outline-none focus:border-[#7c3aed] cursor-pointer transition-colors"
             >
               <option value="race">Course - le premier arrivé gagne</option>
diff --git a/app/components/ScreenRouter.tsx b/app/components/ScreenRouter.tsx
index 07e20cb..905d6ed 100644
--- a/app/components/ScreenRouter.tsx
+++ b/app/components/ScreenRouter.tsx
@@ -158,6 +158,7 @@ export function ScreenRouter({
         setTotalRounds={setTotalRounds}
         gameMode={gameMode}
         setGameMode={setGameMode}
+        onSetGameMode={(v) => multi.setGameMode(v)}
         onSetSearchAllowed={(v) => multi.setSearchAllowed(v)}
         onSetTimeLimit={(v) => multi.setTimeLimit(v)}
       />
diff --git a/lib/useMultiGame.ts b/lib/useMultiGame.ts
index 7252d1a..580fe13 100644
--- a/lib/useMultiGame.ts
+++ b/lib/useMultiGame.ts
@@ -361,6 +361,16 @@ export function useMultiGame() {
   // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [room, playerId]);
 
+  async function setGameMode(value: "race" | "all_finish") {
+    if (!room || !playerId) return;
+    const res = await fetch(`/api/rooms/${room.code}`, {
+      method: "PATCH",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify({ action: "setGameMode", playerId, value }),
+    });
+    if (res.ok) setRoom((await res.json() as { room: Room }).room);
+  }
+
   async function setTimeLimit(value: number) {
     if (!room || !playerId) return;
     const res = await fetch(`/api/rooms/${room.code}`, {
@@ -468,6 +478,7 @@ export function useMultiGame() {
     canGoBack: historyRef.current.length > 1,
     surrender,
     timeLeft,
+    setGameMode,
     setTimeLimit,
     setSearchAllowed,
     restore,