Abstract: Hydraulic control rod drive technology (HCRDT) is a newly invented patent of Institute of Nuclear and New Energy Technology, Tsinghua University which owns HCRDT’s independent intellectual property rights. The integrated valve which is made up of three direct action solenoid valves is the key part of this technology, so the performance of the solenoid valve directly affects the function of the integrated valve and the HCRDT. The parameters of the direct action solenoid valve were designed and analyzed using quadratic regression orthogonal experiment and complex method. The result shows that the current influences the electromagnetic force of the direct action solenoid valve most. Further more, the design parameters of the direct action solenoid valve can be optimized by complex method.