diff --git a/app/but/bulletin_but.py b/app/but/bulletin_but.py
index df9409e5c6..61ee57df15 100644
--- a/app/but/bulletin_but.py
+++ b/app/but/bulletin_but.py
@@ -152,7 +152,7 @@ class ResultatsSemestreBUT:
             mod_idx = self.modimpl_coefs_df.columns.get_loc(mi.id)
             # moyennes indicatives (moyennes de moyennes d'UE)
             moyennes_etuds = np.nan_to_num(
-                self.sem_cube[:, mod_idx, :].mean(axis=1),
+                np.nanmean(self.sem_cube[:, mod_idx, :], axis=1),
                 copy=False,
             )
             d[mi.module.code] = {
@@ -165,7 +165,8 @@ class ResultatsSemestreBUT:
                     moduleimpl_id=mi.id,
                 ),
                 "moyenne": {
-                    "value": fmt_note(self.sem_cube[etud_idx, mod_idx].mean()),
+                    # moyenne indicative de module: moyenne des UE, ignorant celles sans notes (nan)
+                    "value": fmt_note(np.nanmean(self.sem_cube[etud_idx, mod_idx])),
                     "min": fmt_note(moyennes_etuds.min()),
                     "max": fmt_note(moyennes_etuds.max()),
                     "moy": fmt_note(moyennes_etuds.mean()),