diff --git a/composer.json b/composer.json
index 9d7d90398..e45d32eb6 100644
--- a/composer.json
+++ b/composer.json
@@ -32,5 +32,8 @@
         "branch-alias": {
             "dev-master": "1.6.x-dev"
         }
+    },
+    "suggest": {
+        "ext-mbstring": "Only required when ICONTAINS comparison is used"
     }
 }
diff --git a/lib/Doctrine/Common/Collections/Expr/ClosureExpressionVisitor.php b/lib/Doctrine/Common/Collections/Expr/ClosureExpressionVisitor.php
index cd99e2f10..56ca30978 100644
--- a/lib/Doctrine/Common/Collections/Expr/ClosureExpressionVisitor.php
+++ b/lib/Doctrine/Common/Collections/Expr/ClosureExpressionVisitor.php
@@ -163,6 +163,11 @@ public function walkComparison(Comparison $comparison)
                     return strpos(ClosureExpressionVisitor::getObjectFieldValue($object, $field), $value) !== false;
                 };
 
+            case Comparison::ICONTAINS:
+                return function ($object) use ($field, $value) {
+                    return false !== strpos(mb_strtolower(ClosureExpressionVisitor::getObjectFieldValue($object, $field)), mb_strtolower($value));
+                };
+
             case Comparison::MEMBER_OF:
                 return function ($object) use ($field, $value) : bool {
                     $fieldValues = ClosureExpressionVisitor::getObjectFieldValue($object, $field);
diff --git a/lib/Doctrine/Common/Collections/Expr/Comparison.php b/lib/Doctrine/Common/Collections/Expr/Comparison.php
index d93687086..4f7110eee 100644
--- a/lib/Doctrine/Common/Collections/Expr/Comparison.php
+++ b/lib/Doctrine/Common/Collections/Expr/Comparison.php
@@ -7,19 +7,20 @@
  */
 class Comparison implements Expression
 {
-    public const EQ          = '=';
-    public const NEQ         = '<>';
-    public const LT          = '<';
-    public const LTE         = '<=';
-    public const GT          = '>';
-    public const GTE         = '>=';
-    public const IS          = '='; // no difference with EQ
-    public const IN          = 'IN';
-    public const NIN         = 'NIN';
-    public const CONTAINS    = 'CONTAINS';
-    public const MEMBER_OF   = 'MEMBER_OF';
-    public const STARTS_WITH = 'STARTS_WITH';
-    public const ENDS_WITH   = 'ENDS_WITH';
+    public const EQ           = '=';
+    public const NEQ          = '<>';
+    public const LT           = '<';
+    public const LTE          = '<=';
+    public const GT           = '>';
+    public const GTE          = '>=';
+    public const IS           = '='; // no difference with EQ
+    public const IN           = 'IN';
+    public const NIN          = 'NIN';
+    public const CONTAINS     = 'CONTAINS';
+    public const ICONTAINS    = 'ICONTAINS';
+    public const MEMBER_OF    = 'MEMBER_OF';
+    public const STARTS_WITH  = 'STARTS_WITH';
+    public const ENDS_WITH    = 'ENDS_WITH';
 
     /**
      * @var string
diff --git a/lib/Doctrine/Common/Collections/ExpressionBuilder.php b/lib/Doctrine/Common/Collections/ExpressionBuilder.php
index 55a95e6b6..a0669e57d 100644
--- a/lib/Doctrine/Common/Collections/ExpressionBuilder.php
+++ b/lib/Doctrine/Common/Collections/ExpressionBuilder.php
@@ -145,6 +145,17 @@ public function contains($field, $value)
         return new Comparison($field, Comparison::CONTAINS, new Value($value));
     }
 
+    /**
+     * @param string $field
+     * @param mixed  $value
+     *
+     * @return Comparison
+     */
+    public function iContains($field, $value)
+    {
+        return new Comparison($field, Comparison::ICONTAINS, new Value($value));
+    }
+
     /**
      * @param string $field
      * @param mixed  $value
diff --git a/tests/Doctrine/Tests/Common/Collections/ExpressionBuilderTest.php b/tests/Doctrine/Tests/Common/Collections/ExpressionBuilderTest.php
index eba0a97ab..86e812103 100644
--- a/tests/Doctrine/Tests/Common/Collections/ExpressionBuilderTest.php
+++ b/tests/Doctrine/Tests/Common/Collections/ExpressionBuilderTest.php
@@ -124,6 +124,14 @@ public function testContains() : void
         self::assertEquals(Comparison::CONTAINS, $expr->getOperator());
     }
 
+    public function testIContains() : void
+    {
+        $expr = $this->builder->iContains("a", "b");
+
+        $this->assertInstanceOf(Comparison::class, $expr);
+        $this->assertEquals(Comparison::ICONTAINS, $expr->getOperator());
+    }
+
     public function testMemberOf() : void
     {
         $expr = $this->builder->memberOf('b', ['a']);