diff --git a/aitrainer_backoffice/aitrainer_backoffice/models.py b/aitrainer_backoffice/aitrainer_backoffice/models.py
index b1afada..5d4ed37 100644
--- a/aitrainer_backoffice/aitrainer_backoffice/models.py
+++ b/aitrainer_backoffice/aitrainer_backoffice/models.py
@@ -3,7 +3,7 @@ from django.utils.translation import ugettext_lazy as _
 
 
 class ExerciseTree(models.Model):
-    item_id = models.AutoField(primary_key=True)
+    tree_id = models.AutoField(primary_key=True)
     parent_id = models.IntegerField(help_text='This is the parent menu ID. 0 if it is on the top of the tree')
     name = models.CharField(max_length=100, help_text='The name should be in English here')
     image_url = models.ImageField(upload_to='images/', help_text='The menu image size is 1366x768')