Abstract: In order to solve the problem of burr removal at the cross hole of the internal cavity of the hydraulic valve, this paper established the physical model of burr removing machining and the formula of the dissolution rate of anode, which were based on the theory of electrochemical machining. Aiming at the burr of the intersecting hole of 45 steel drilling, the paper carried out the single factor test and the orthogonal test, which revealed the influence of voltage, machining time and the inlet pressure of the electrolyte on the residual height of the burr, and processed the workpiece which meets the machining requirements. This paper has a certain reference value to actual production.