Abstract: Aiming at the dependency of the gait recognition algorithms on the time alignment and the gait cycle extraction, a novel gait representation is proposed. The spatio-temporal energy (STE) image and the wavelet transformation (WT) are used to deal with the problem of time-dependence and time-invariant covariation. The extracted features cover the physiological characteristics and the behavior characteristics. Recognition results demonstrate that the method has good performance, as well as the merit of low space and time requirement.