diff --git a/erpnext/education/doctype/student_group/student_group.py b/erpnext/education/doctype/student_group/student_group.py
index aa542dd..9ec9438 100644
--- a/erpnext/education/doctype/student_group/student_group.py
+++ b/erpnext/education/doctype/student_group/student_group.py
@@ -26,6 +26,8 @@
 			frappe.throw(_("Please select Program"))
 
 	def validate_strength(self):
+		if self.max_strength < 0:
+			frappe.throw(_("""Cannot enroll less than 0 students for this student group."""))
 		if self.max_strength and len(self.students) > self.max_strength:
 			frappe.throw(_("""Cannot enroll more than {0} students for this student group.""").format(self.max_strength))