Abstract: In order to solve the matching problem between drilling parameters and formation quickly and conveniently for raising-boring machine, firstly, based on the theory of rock crushing energy and the Rosin-Rammler distribution mechanism of ballast, the theoretical analysis shows that the characteristic particle size has Gaussian distribution relationship with the pressure under the Kick's similarity theory, and it has reciprocal quadratic function relationship with the pressure under the Bond's crack theory and the Riginger's new surface theory. Thus, the theory of the characteristic particle size under the optimal drilling pressure of insert cutters is obtained through the rock ballast analysis. Then, through the linear cutting tests on the insert cutter with six rows of picks, the theory of the characteristic particle size is verified, and it is proved that it has a good applicability for analyzing the above cutter using the Kick's similarity theory and the Bond's crack theory. The pressures obtained by the above two methods when the characteristic particle size is the largest are the optimal ones obtained by using the minimum specific energy method. In order to improve the fitting accuracy using the Bond's crack theory, the Gaussian function can also be used to fit the theory of the characteristic particle size. Finally, the theory of the characteristic particle size is put into practice in Baihetan raising-boring project, and its applicability in the construction site is verified.