In the permanent magnet synchronous motor (PMSM) double-closed-loop speed control system, the current loop as the inner loop restricts the dynamic responsiveness of the control system directly. Deadbeat predictive current control (DPCC) has the advantages of simple algorithm and fast dynamic response, but DPCC requires an accurate motor model. The mismatch of parameters can cause current static error and distortion, especially the mismatch of inductance. It can cause instability of the control system. To solve the above problems, an improved DPCC algorithm is proposed. The discrete transfer function of traditional DPCC is deduced, and the influence of its parameter sensitivity is analyzed. The DPCC algorithm is further improved to achieve better inductance parameter sensitivity, effectively expand the applicable range of inductance, and reduce current distortion. The effectiveness of the improved DPCC under inductance mismatch is verified by MATLAB/Simulink simulation and experiments.