Abstract: This paper first introduces the file system——UDF（Universal Disc Format), which has been widely used in disc storage.
The constitution and the strengths and weaknesses of UDF have also been discussed. This paper proposes a method of increasing the basic information partition and the imprint information partition to improve the scanning rate and reliability. The optimized UDF file system performs high fault toleration and time performance after the practical application.

Key words: file system, UDF, scanning rate, reliability