diff --git a/lerobot/common/envs/aloha/env.py b/lerobot/common/envs/aloha/env.py
index 22cd0116..bd14e6d8 100644
--- a/lerobot/common/envs/aloha/env.py
+++ b/lerobot/common/envs/aloha/env.py
@@ -48,8 +48,15 @@ class AlohaEnv(gym.Env):
                 dtype=np.float64,
             )
         elif self.obs_type == "pixels":
-            self.observation_space = spaces.Box(
-                low=0, high=255, shape=(self.observation_height, self.observation_width, 3), dtype=np.uint8
+            self.observation_space = spaces.Dict(
+                {
+                    "top": spaces.Box(
+                        low=0,
+                        high=255,
+                        shape=(self.observation_height, self.observation_width, 3),
+                        dtype=np.uint8,
+                    )
+                }
             )
         elif self.obs_type == "pixels_agent_pos":
             self.observation_space = spaces.Dict(