A multi-tooth cutting head of a hard rock tunneling machine comprises a cutting head mounting frame and a plurality sets of cutting mechanisms. The cutting mechanisms are circumferentially arranged onthe cutting head mounting frame and are centralizedly inclined towards the central axis of the cutting head, so that the cutting head is overall in a cone shape. The cutting head mounting frame is connected with a power output shaft in a cutting arm in a matched mode through a mounting hole in the center inside the cutting head mounting frame. The multi-tooth cutting head can be conveniently andeffectively mounted on the cantilever-type cutting arm of the tunneling machine, the drilling technology and the transverse pendulum cutting process of the tunneling machine can be completed, the hardrock tunneling effect is good, and the problems of difficult and slow construction of a hard rock roadway are effectively solved.