Abstract: To track harmonic current accurately in the nine-phase open-end winding permanent magnet synchronous motors (PMSM), this paper proposes a harmonic current model predictive control method. According to the distribution of voltage vectors in the harmonic subspaces, this method designs virtual voltage vectors (VVV) in third harmonic subspace, which is based on the criterion of minimizing switch state switching. Then, to overcome the optimization problem of overlapping spatial distribution of third harmonic VVVs, this paper proposes an improved method for selecting the optimal vector in harmonic space, while simplifying the optimization calculation process. Finally, the feasibility of the proposed method is verified by experiments. The experimental results show that the proposed method provides effective harmonic current control without increasing the switching frequency.