Currently, XML data is stored either in traditional file system or certain database storage systems. But both have their disadvantages. Traditional file systems can not support query engines directly, while database storage systems are quite expensive for read-only XML query systems. We propose a new XML semantic file system to serve both regular query requests from query/search engines and file requests from file system users. It provides DOM interface to database query engine and can help user search XML files by queries. Experiments demonstrate that our system has small disk overhead and it is efficient in processing user queries.