This paper proposes an improved model predictive control (MPC) method for a five-leg voltage source inverter (FLVSI) that drives the dual three-phase induction motor system. The conventional MPC method using the full-set voltage vectors (FSMPC) has high computational burden. To reduce the computational burden, the other conventional MPC method considering only the adjacent voltage vectors (A-MPC) stored in the lookup table (LUT) is introduced but increases the current ripple causing degradation of the control performance compared to FSMPC. Therefore, in this paper, the improved MPC is proposed to reduce the computational complexity and improve the control performance compared to A-MPC. Additionally, the proposed method is compared with the conventional methods (FSMPC, A-MPC) and its effectiveness is verified by simulation results.