Abstract: In order to solve the deformation problem of dynamic pressure roadway under the influence of thick and hard roof, this paper comprehensively studies the directional presplitting roof cutting pressure relief technology and its key parameters, including roof cutting angle, height, blast hole charge and spacing, by using the research methods of theoretical analysis, numerical simulation and engineering test. Based on the engineering geological conditions of the test face in caojiatan mine, the numerical simulation and field test of roof cutting and pressure relief are carried out, and the reasonable parameters of roof cutting and pressure relief are determined. The research results show that under the condition of directional blasting roof cutting, the deformation of dynamic pressure roadway can be effectively controlled, the bottom heave of the first two supports can be reduced by 50%, the bottom heave of the last four supports can be reduced by more than 91%, and the surrounding rock deformation of thick and hard roof roadway can be effectively controlled.