Mo films were successfully deposited by DC magnetron sputtering on Si substrates. The influences of deposition rate, surface tomograph and microstructure were analyzed. The results show that deposition rate increases with pressure.The film sputtered at low pressure has good crystallization and exhibites dense structure. Under high pressure conditions, the film exhibites bad crystallization and loose structure. At the pressure of 0 . 8 Pa, the film has lowest value of crysize and microstrain.