Abstract: In order to optimize the structure of PDC bits and improve their breaking performance in hard formations, this paper analyzed the influences of cutting angle, cone apex angle, weight on bit (WOB) and other factors of rock breaking of conical PDC cutter, through experiment with basalt.The results showed that the conical cutter was better to be installed on the bit with its prong pointing the bit axis.With the increase of the cutting angle, the cutting depth increased first and then decreased-to the maximum when the cutting angle was 25°.The conical PDC cutter with small cone apex angle required smaller force to break the same volume of rock and the cutting depth increased with the WOB exponentially.The experimental results could provide reference for the design of a conical PDC bit.