diff --git a/runbot/models/build_error.py b/runbot/models/build_error.py
index 438e5a6d..be9686dd 100644
--- a/runbot/models/build_error.py
+++ b/runbot/models/build_error.py
@@ -19,7 +19,7 @@ class BuildErrorLink(models.Model):
     _order = 'log_date desc, build_id desc'
 
     build_id = fields.Many2one('runbot.build', required=True, index=True)
-    build_error_id =fields.Many2one('runbot.build.error', required=True, index=True)
+    build_error_id =fields.Many2one('runbot.build.error', required=True, index=True, ondelete='cascade')
     log_date = fields.Datetime(string='Log date')
     host = fields.Char(related='build_id.host')
     dest = fields.Char(related='build_id.dest')