diff --git a/erpnext/stock/doctype/item/item.js b/erpnext/stock/doctype/item/item.js
index 24d3659f576..2503cd0148e 100644
--- a/erpnext/stock/doctype/item/item.js
+++ b/erpnext/stock/doctype/item/item.js
@@ -230,7 +230,7 @@ frappe.ui.form.on("Item", {
 		].forEach((fieldname) => {
 			frm.set_df_property(fieldname, "read_only", stock_exists);
 		});
-
+		frm.set_df_property("is_fixed_asset", "read_only", frm.doc.__onload?.asset_exists ? 1 : 0);
 		frm.toggle_reqd("customer", frm.doc.is_customer_provided_item ? 1 : 0);
 		frm.set_query("item_group", () => {
 			return {
diff --git a/erpnext/stock/doctype/item/item.json b/erpnext/stock/doctype/item/item.json
index 2d6fb2c3a58..8d2f24420c3 100644
--- a/erpnext/stock/doctype/item/item.json
+++ b/erpnext/stock/doctype/item/item.json
@@ -247,8 +247,7 @@
    "default": "0",
    "fieldname": "is_fixed_asset",
    "fieldtype": "Check",
-   "label": "Is Fixed Asset",
-   "set_only_once": 1
+   "label": "Is Fixed Asset"
   },
   {
    "allow_in_quick_entry": 1,
@@ -917,7 +916,7 @@
  "image_field": "image",
  "links": [],
  "make_attachments_public": 1,
- "modified": "2025-11-03 17:01:24.555003",
+ "modified": "2025-12-04 09:11:56.029567",
  "modified_by": "Administrator",
  "module": "Stock",
  "name": "Item",
diff --git a/erpnext/stock/doctype/item/item.py b/erpnext/stock/doctype/item/item.py
index fc973ac2449..a707a0a4bc3 100644
--- a/erpnext/stock/doctype/item/item.py
+++ b/erpnext/stock/doctype/item/item.py
@@ -156,6 +156,7 @@ class Item(Document):
 		self.set_onload("stock_exists", self.stock_ledger_created())
 		self.set_onload("asset_naming_series", get_asset_naming_series())
 		self.set_onload("current_valuation_method", get_valuation_method(self.name))
+		self.set_onload("asset_exists", self.has_submitted_assets())
 
 	def autoname(self):
 		if frappe.db.get_default("item_naming_by") == "Naming Series":
@@ -308,8 +309,7 @@ class Item(Document):
 				frappe.throw(_("Cannot be a fixed asset item as Stock Ledger is created."))
 
 		if not self.is_fixed_asset and not self.is_new():
-			asset = frappe.db.get_all("Asset", filters={"item_code": self.name, "docstatus": 1}, limit=1)
-			if asset:
+			if self.has_submitted_assets():
 				frappe.throw(
 					_('"Is Fixed Asset" cannot be unchecked, as Asset record exists against the item')
 				)
@@ -524,6 +524,9 @@ class Item(Document):
 			)
 		return self._stock_ledger_created
 
+	def has_submitted_assets(self):
+		return bool(frappe.db.exists("Asset", {"item_code": self.name, "docstatus": 1}))
+
 	def update_item_price(self):
 		if self.is_new():
 			return