The corrosion resistance of aluminum (Al) cable-copper (Cu) terminal joints fabricated by magnetic pulse crimping (MPC) and hydraulic clamp crimping (HCC) was compared. Performance degradation was evaluated by mechanical and electrical properties. Additionally, corrosion behavior was analyzed by electrochemical testing. Microscopic characterization was performed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Results show that the tensile strength of the corroded joints is reduced. However, due to the advantages of high-speed forming and contact tightness unique to MPC, the contact resistance of the corroded joints still maintains excellent. Electrochemical tests demonstrate that the MPC joints have higher corrosion potentials and smaller corrosion currents, providing better corrosion resistance. The formation of a primary battery between Al and Cu at the lap joint leads to the formation of severer corrosion pits.