Rotary percussion drilling is an important method of drilling and widely used in geological exploration. Traditionally in rotary percussion drilling application of impact pulse is centric，but not eccentric. Russian experts have put award fragmentation of rock by application of eccentric impact pulse in order to improve the result of the fragmentation. That is a new concept and an innovation. They have done experimental research on it. It has been proved, that in rotary percussion drilling by eccentric impact pules in rock noy only vertical normal stress are created、but also tangential shear stress created and it is beneficial to improve the result of rock fragmentation and rising of drilling rate. In drilling dolerite and marble at eccentricity E=1mm-2 mm the mechanical drilling rate and bit penetration per revolution are increased substantially in comparison with E=0 mm. Matching with the mentioned above the drill bit for eccentric rotary percussion drilling has been developed and the bit patent obtained, strengthening the result and role of the eccentric rotary percussion drilling further in geological exploration.