In view of the complex structure and high processing difficulty of the stator mold core of the elliptical screw pump, by studying the forming principle of the stator line of the elliptical screw pump, the contour line of the stator mold core was determined, the structural characteristics of the contour line of the stator mold core were analyzed, and two different forming tools were determined for the processing of the stator mold core. The forming milling cutter profile was designed according to end section,there was interference when machining.The method of stator section cross-sectional shape was used to design forming tool,and the stator mold core helical surface equation was built through coordinate transformation. It was combined with the contact condition to solve the contact equation,then formed milling cutter profile was obtained.The interference check between tool and workpiece was made based on curvature radius. It verifies the correctness of the blade profile.The research provides a theoretical basis for the contour design of the milling cutter for forming the stator core of the elliptical screw pump.