Because of the advantages of low average power, high recurrence frequency and low coherence requirement for light sources, pulse laser ranging technology has wide applications in military industry. The precision of the pulse laser ranging technology can be improved directly by improving the time-gap measurement accuracy in pulse laser ranging. In order to reach the ps-level measurement accuracy, a single chip microcomputer is used to control a time measurement chip. So, the time measurement chip not only can measure the time delay between the emitted pulse signal and the returned pulse signal, but also can correct the measurement result automatically. Compared with the traditional methods for measuring the time-gap in pulse laser ranging, this method can simplify the design of a device and improve its measurement speed.