Abstract: The stick-slip vibration of PDC bit is one of the main factors leading to abnormal wear of the bit during deep and ultra-deep wells drilling. In this paper, the laboratory research on rock drilling stick-slip vibration of PDC bit is carried out by impact rock drilling device. And this device assembles the axial disc spring loading module and torsional elastic rod module to simulate the axial stiffness and torsional stiffness of the drill pipe, respectively. The device is also equipped with an axial-torsional composite impact module, so the influences of the combined axial-torsional impact load on the stick-slip vibration of PDC bit during drilling are also studied. The research results show that the elastic loading module used in the laboratory rock drilling device can simulate the stick-slip vibration phenomenon in the field PDC bit well drilling. The stick-slip vibration of PDC bit will be enhanced obviously with the increase of triping speed under the condition of fixed driving rotation speed. When the average weight on bit is 20.12kN, the corresponding maximum slip speed is more than 2.5 times the driving rotation speed, and the stick-slip ratio is 1.31, with intermittent rotation stagnation. The main frequency of the stick-slip vibration is the first-order natural frequency of the torsional loading module of the laboratory rock drilling device. The combined impact can significantly reduce the slip-slip phenomenon of PDC bit drilling, which is represented by the significant reduction of the rotation speed amplitude at the main frequency, and the combined impact of 50Hz and 100Hz has the most obvious inhibition on stick-slip vibration of this laboratory rock drilling device.