In this study, a step-detection method for the time synchronization of short pulses, based on spatial-spectral interference and far field, is proposed. A large range of time synchronization is first captured using the spatial-spectral interference, and the high-precision detection of which is then realized using far field. The proposed method is then simulated and analyzed. Results show the feasibility of this proposed method, suggesting that it exhibits advantages such as a large range and high precision. Moreover, the low requirement of energy makes it suitable for a short-pulse laser system as most of the energy can be applied to physical experiments. Furthermore, it can be used for the measurement and control of the time synchronization in plasma parameter diagnosis, coherent beam combination, and other fields.