Abstract: Based on the externally breaking stone with impact wave and the theory of pulsative oscillation jet nozzle, the electric-hydraulic pulse method can be used to clean the scale deposit on the internal surface of pipe of the gathering pipeline in oilfield. To generate the electric-hydraulic pressure effect, the four necessary conditions must be provided: ① an additional clearence; ② a big current amplitude; ③ a high current slope; ④ a short wave tail. The simplified equations in calculating wavefront pressure of pressure wave formed in liquid discharge are put forward, and general application program of this method is given.