To design spool thermal control valve(TCV)with small flow resistance and axial fluid force,parameters of V-groove spool valve were chosen by using Latin hypercube sampling method.Through the simulation of spacecraft fluid loop system,equal percentage type spool valve’〖KG-*2〗s overshoot was considered to be the smallest.This kind of spool valve was chosen as equal percentage type spool valve.The design was optimized by valve core and cage’〖KG-*2〗s parameters and significant to quantified design of spool TCV.