diff --git a/common/djangoapps/student/migrations/0050_coursenrollment_rm_user_foreign_db_constraint.py b/common/djangoapps/student/migrations/0050_coursenrollment_rm_user_foreign_db_constraint.py
new file mode 100644
index 000000000000..3f57f3305292
--- /dev/null
+++ b/common/djangoapps/student/migrations/0050_coursenrollment_rm_user_foreign_db_constraint.py
@@ -0,0 +1,26 @@
+# rm user foreign key db constraint to avoid deadlocks when deleting users.
+
+from django.conf import settings
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+        ('student', '0049_manualenrollmentaudit_statetransition_typo'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='courseenrollment',
+            name='user',
+            field=models.ForeignKey(db_constraint=False, on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL),
+        ),
+        migrations.AlterField(
+            model_name='courseenrollmentallowed',
+            name='user',
+            field=models.ForeignKey(blank=True, db_constraint=False, help_text="First user which enrolled in the specified course through the specified e-mail. Once set, it won't change.", null=True, on_delete=django.db.models.deletion.CASCADE, to=settings.AUTH_USER_MODEL),
+        ),
+    ]
diff --git a/common/djangoapps/student/models/course_enrollment.py b/common/djangoapps/student/models/course_enrollment.py
index cbf257b77f46..1c3b35dc104a 100644
--- a/common/djangoapps/student/models/course_enrollment.py
+++ b/common/djangoapps/student/models/course_enrollment.py
@@ -307,7 +307,7 @@ class CourseEnrollment(models.Model):
     """
     MODEL_TAGS = ['course', 'is_active', 'mode']
 
-    user = models.ForeignKey(User, on_delete=models.CASCADE)
+    user = models.ForeignKey(User, on_delete=models.CASCADE, db_constraint=False)
 
     course = models.ForeignKey(
         CourseOverview,
@@ -1611,6 +1611,7 @@ class CourseEnrollmentAllowed(DeletableByUserValue, models.Model):
         help_text="First user which enrolled in the specified course through the specified e-mail. "
                   "Once set, it won't change.",
         on_delete=models.CASCADE,
+        db_constraint=False,
     )
 
     created = models.DateTimeField(auto_now_add=True, null=True, db_index=True)