diff --git a/docs/en/sql-reference/functions/functions-for-nulls.md b/docs/en/sql-reference/functions/functions-for-nulls.md
index c32af7194fb..fbbda2c0ecc 100644
--- a/docs/en/sql-reference/functions/functions-for-nulls.md
+++ b/docs/en/sql-reference/functions/functions-for-nulls.md
@@ -13,6 +13,8 @@ Checks whether the argument is [NULL](../../sql-reference/syntax.md#null-literal
 isNull(x)
 ```
 
+Alias: `ISNULL`.
+
 **Parameters**
 
 -   `x` — A value with a non-compound data type.
diff --git a/docs/ru/sql-reference/functions/functions-for-nulls.md b/docs/ru/sql-reference/functions/functions-for-nulls.md
index 17da1ea9194..0db55847631 100644
--- a/docs/ru/sql-reference/functions/functions-for-nulls.md
+++ b/docs/ru/sql-reference/functions/functions-for-nulls.md
@@ -13,6 +13,8 @@ toc_title: "\u0424\u0443\u043d\u043a\u0446\u0438\u0438\u0020\u0434\u043b\u044f\u
 isNull(x)
 ```
 
+Синоним: `ISNULL`.
+
 **Параметры**
 
 -   `x` — значение с не составным типом данных.