In the traditional development process of electric locomotive traction control software, there existed problems such as high labor costs, inconsistent development standards, difficult software verification, and high software maintenance costs. MBD (Model-Based-Design) and the automatic code generation technology were mostly used in the field of automotive electronics, promoted in several mainstream automobile factories, but had hardly ventured into the field of rail transit. The MBD method was applied to the development process of electric locomotive traction control software, to realize the model-based traction control logic and algorithm development in the MATLAB platform. The paper shows the process of designing the traction control model, generating the code and being downloaded to the traction control unit automatically, finally, testing the system with HIL (Hardware-In-Loop) semi-physical simulation. The four-quadrant waveforms met the design requirements. The results showed that it was feasible, efficient and economical to design the four-quadrant control software of the traction converter by the MBD method.