diff --git a/tests/phpunit/tests/blocks/serialization.php b/tests/phpunit/tests/blocks/serialization.php
new file mode 100644
index 0000000000..48ee778b82
--- /dev/null
+++ b/tests/phpunit/tests/blocks/serialization.php
@@ -0,0 +1,60 @@
+<?php
+/**
+ * Block serialization tests.
+ *
+ * @package WordPress
+ * @subpackage Blocks
+ * @since 5.3.3
+ */
+
+/**
+ * Tests for block serialization functions
+ *
+ * @since 5.3.3
+ *
+ * @group blocks
+ */
+class WP_Test_Block_Serialization extends WP_UnitTestCase {
+
+	/**
+	 * @dataProvider data_serialize_identity_from_parsed
+	 */
+	function test_serialize_identity_from_parsed( $original ) {
+		$blocks = parse_blocks( $original );
+
+		$actual   = serialize_blocks( $blocks );
+		$expected = $original;
+
+		$this->assertEquals( $expected, $actual );
+	}
+
+	function data_serialize_identity_from_parsed() {
+		return array(
+			// Void block.
+			array( '<!-- wp:void /-->' ),
+
+			// Freeform content ($block_name = null).
+			array( 'Example.' ),
+
+			// Block with content.
+			array( '<!-- wp:content -->Example.<!-- /wp:content -->' ),
+
+			// Block with attributes.
+			array( '<!-- wp:attributes {"key":"value"} /-->' ),
+
+			// Block with inner blocks.
+			array( "<!-- wp:outer --><!-- wp:inner {\"key\":\"value\"} -->Example.<!-- /wp:inner -->\n\nExample.\n\n<!-- wp:void /--><!-- /wp:outer -->" ),
+
+			// Block with attribute values that may conflict with HTML comment.
+			array( '<!-- wp:attributes {"key":"\\u002d\\u002d\\u003c\\u003e\\u0026\\u0022"} /-->' ),
+		);
+	}
+
+	function test_serialized_block_name() {
+		$this->assertEquals( null, strip_core_block_namespace( null ) );
+		$this->assertEquals( 'example', strip_core_block_namespace( 'example' ) );
+		$this->assertEquals( 'example', strip_core_block_namespace( 'core/example' ) );
+		$this->assertEquals( 'plugin/example', strip_core_block_namespace( 'plugin/example' ) );
+	}
+
+}