With the floppy drive and floppy disk decrease, the equipment which have to use them are facing a rigorous problem, at this time the FDD-UDD present to our sight. It is compatible to the floppy drive’s interface, consumer can make use of it by connect the FDD-UDD to the computer, let the USB Flash Drive to instead of floppy disk, avoiding a great deal of defects the floppy disk has. For mainboard, it is similar with the traditional floppy drive, insert the 34 pin FDC on mainboard, it can be used as the floppy drive, and the application software is no need to modify. For consumer, actually their use is USB Flash Drive but not floppy disk, compare the USB Flash Drive to floppy disk, the USB Flash Drive has a lot of advantage such as: smaller, carry easily, more length of service, diamagnetism, mould proof and aseismatic.