diff --git a/docs/en/expression-builder.rst b/docs/en/expression-builder.rst
index e0224418..043b89cc 100644
--- a/docs/en/expression-builder.rst
+++ b/docs/en/expression-builder.rst
@@ -124,6 +124,16 @@ isNull
 
     $collection->matching(new Criteria($expression));
 
+isNotNull
+---------
+
+.. code-block:: php
+    $expressionBuilder = Criteria::expr();
+
+    $expression = $expressionBuilder->isNotNull('foo');
+
+    $collection->matching(new Criteria($expression));
+
 in
 ---
 
diff --git a/src/ExpressionBuilder.php b/src/ExpressionBuilder.php
index fc25e3a9..7bf5a09a 100644
--- a/src/ExpressionBuilder.php
+++ b/src/ExpressionBuilder.php
@@ -77,6 +77,11 @@ public function isNull(string $field)
         return new Comparison($field, Comparison::EQ, new Value(null));
     }
 
+    public function isNotNull(string $field): Comparison
+    {
+        return new Comparison($field, Comparison::NEQ, new Value(null));
+    }
+
     /**
      * @param mixed[] $values
      *
diff --git a/tests/ExpressionBuilderTest.php b/tests/ExpressionBuilderTest.php
index cfba7626..1c272938 100644
--- a/tests/ExpressionBuilderTest.php
+++ b/tests/ExpressionBuilderTest.php
@@ -114,6 +114,14 @@ public function testIsNull(): void
         self::assertEquals(Comparison::EQ, $expr->getOperator());
     }
 
+    public function testIsNotNull(): void
+    {
+        $expr = $this->builder->isNotNull('a');
+
+        self::assertInstanceOf(Comparison::class, $expr);
+        self::assertEquals(Comparison::NEQ, $expr->getOperator());
+    }
+
     public function testContains(): void
     {
         $expr = $this->builder->contains('a', 'b');