diff --git a/erpnext/accounts/doctype/accounting_dimension/accounting_dimension.json b/erpnext/accounts/doctype/accounting_dimension/accounting_dimension.json
index cf55d554fb..5858f10bb0 100644
--- a/erpnext/accounts/doctype/accounting_dimension/accounting_dimension.json
+++ b/erpnext/accounts/doctype/accounting_dimension/accounting_dimension.json
@@ -30,6 +30,7 @@
    "fieldtype": "Link",
    "label": "Reference Document Type",
    "options": "DocType",
+   "read_only_depends_on": "eval:!doc.__islocal",
    "reqd": 1
   },
   {
@@ -48,7 +49,7 @@
   }
  ],
  "links": [],
- "modified": "2020-03-22 20:34:39.805728",
+ "modified": "2021-02-08 16:37:53.936656",
  "modified_by": "Administrator",
  "module": "Accounts",
  "name": "Accounting Dimension",
diff --git a/erpnext/accounts/doctype/accounting_dimension/accounting_dimension.py b/erpnext/accounts/doctype/accounting_dimension/accounting_dimension.py
index ef0d3a3cb1..dd26c4cec2 100644
--- a/erpnext/accounts/doctype/accounting_dimension/accounting_dimension.py
+++ b/erpnext/accounts/doctype/accounting_dimension/accounting_dimension.py
@@ -29,6 +29,16 @@ class AccountingDimension(Document):
 		if exists and self.is_new():
 			frappe.throw("Document Type already used as a dimension")
 
+		if not self.is_new():
+			self.validate_document_type_change()
+
+	def validate_document_type_change(self):
+		doctype_before_save = frappe.db.get_value("Accounting Dimension", self.name, "document_type")
+		if doctype_before_save != self.document_type:
+			message = _("Cannot change Reference Document Type.")
+			message += _("Please create a new Accounting Dimension if required.")
+			frappe.throw(message)
+
 	def after_insert(self):
 		if frappe.flags.in_test:
 			make_dimension_in_accounting_doctypes(doc=self)