In this paper, the effect of the lubricating action of PTFE on the wear mechanism of the bronze filled PTFE composite, which is applicable to the machine tool slideway, is studied. The results of the analyses are as follows: (1) From the wear tests of the bronze which is lubricated by PTFE, it is proved that the wear rate of the bronze can be decreased by increasing the supply of PTFE and/or by reducing the load to the bronze. (2) By the use of the result (1), the wear rate of the bronze filled PTFE composite is derived theoretically, and this theoretical analysis shows good agreement with the experimental result. (3) Heavy adhesion of PTFE film to the surface of the composite is almost always observed with a microscope. This observation and the results of the wear tests indicate that the PTFE film prevents the direct contacts between the fillers and the counter face, and such lubricating action of PTFE decreases the wear rate of the fillers.