diff --git a/src/Schema/Keywords/Pattern.php b/src/Schema/Keywords/Pattern.php
index ccf91655..be405cc2 100644
--- a/src/Schema/Keywords/Pattern.php
+++ b/src/Schema/Keywords/Pattern.php
@@ -38,7 +38,7 @@ public function validate($data, string $pattern): void
             throw InvalidSchema::becauseDefensiveSchemaValidationFailed($e);
         }
 
-        $pattern = sprintf('#%s#', str_replace('#', '\#', $pattern));
+        $pattern = sprintf('#%s#u', str_replace('#', '\#', $pattern));
 
         if (! preg_match($pattern, $data)) {
             throw KeywordMismatch::fromKeyword('pattern', $data, sprintf('Data does not match pattern \'%s\'', $pattern));
diff --git a/tests/Schema/Keywords/PatternTest.php b/tests/Schema/Keywords/PatternTest.php
index 2a33bdca..3079a44e 100644
--- a/tests/Schema/Keywords/PatternTest.php
+++ b/tests/Schema/Keywords/PatternTest.php
@@ -22,6 +22,7 @@ public function validDataProvider(): array
             ['1foo1', '1foo1'], // Tests adding anchors when first and last character is same with numbers
             ['^#\d+$', '#123'], // Tests adding anchors to string which has #
             ['^#(\d+)#$', '#123#'], // Tests adding anchors to string which has multiple#
+            ['^[А-Я]{2}$', 'ДГ'], // Tests patterns with Unicode
         ];
     }