With the high accuracy requirement of the guide-localization of the distribute valve,the manufacture of the valve is more difficult when the design of positive opening at the zero position is used in the hydraulic rock drill,and the leakage of the drill is larger,which reduces the working efficiency of the hydraulic rock drill.So a design approach to the negative opening at the zero position and a computing method for the pressure increment of it were put forward to solve this problem on the basis of an analysis and comparison of advantages and disadvantages of the positive opening and negative opening at the zero position respectively.The mathematical model of the valve whose opening was at zero position was therefore established based on the coupling of the accumulator and local resistance.Through the mathematical model,the non-linear equation of the opening motion of the core was obtained.The kinematics of the opening motion at zero position of the valve was simulated in Simulink to analyze and compare the influence of different opening types on the impact property and the pressure of the drill. Compared with the experiment result,the simulation result was verified.The results showed that the design of the negative opening at the zero position of the distribute valve of the hydraulic rock drill optimized the way of guide-localization and reduced the manufacturing difficulties,in addition,the working efficiency of the hydraulic rock drill was increased by 9.2% and the impact energy at a time was increased by 12.5%.Considering the high reliability and efficiency,the design of the negative opening at the zero position is finally selected to be used in the actual working conditions.