Aiming at the problems of DTW algorithm in gesture authentication, the dynamic gesture authentication method for smartphones based on CM-DTW (Constraints Multi-dimensional Dynamic Time Wrapping) is proposed. The method uses smartphone built-in sensors to obtain gesture data which representing users' biological behavior characteristics. The candidate template set of legitimate users is selected by DTW algorithm with Sakoe-Chiba window constraints, and a standard template is obtained by normalizing the candidate template with linear up-down sampling. Compared with DTW algorithm, the proposed method not only improves the time efficiency of user identity authentica-tion but also maintains the accuracy.