The structural principle and main performance parameters of the rotary-percussive PDM are elaborated in this paper. With the combination of impact rock crushing with shear rock cutting of the PDC bit, the tool can provide both the advantages of percussion drilling and PDM drilling, and improve the drill bit’s working performance, resulting in higher ROP. It can also reduce drag forces; thus increasing directional drilling efficiency. The tool impact force has a positive correlation with the weight on bit while the impact frequency is directly proportional to the motor rpm. Tests of the φ178mm drilling motors have been carried out in drilling vertical and directional wells in Linpan Oilfield respectively. ROP in compound drilling was improved by 22.1%～41.8% compared with that of the adjacent well, while the slide drilling ROP was increased by 51.1%, which is of positive significance for speeding up the oilfield exploration and development and reducing drilling cost consequently.