The FLASH memorizer is an important part of the embedded systemswhich has found wide application in engineering.It is very convenient for the users to use the FLASH memorizer by developing the FLASH file systemsuch as copyingdeleting and creating.The TFFS configuration of FLASH under VxWorks operation system is discussed in detail,and how to realize the file system on FLASH memorizer is presented by taking W78M32VP chip as an example for working out the practical problem that the file system can be not formatted.