diff --git a/frappe/core/doctype/doctype/doctype.py b/frappe/core/doctype/doctype/doctype.py
index 27e0ab8209..d8e994d0da 100644
--- a/frappe/core/doctype/doctype/doctype.py
+++ b/frappe/core/doctype/doctype/doctype.py
@@ -1090,6 +1090,12 @@ def validate_series(dt, autoname=None, name=None):
 					df.unique = 1
 					break
 
+	if autoname and autoname.startswith("format:"):
+		from frappe.model.naming import BRACED_PARAMS_HASH_PATTERN
+
+		if len(BRACED_PARAMS_HASH_PATTERN.findall(autoname)) > 1:
+			frappe.throw(_("Only one set of {#} pattern is allowed in the format string"))
+
 	if (
 		autoname
 		and (not autoname.startswith("field:"))