The time jitter of nanosecond semiconductor laser (LD) and the time synchronization of multiple LD parallel triggers are important parameters in various ultra-fast photoelectric processes and applications. In this paper, the time jitter characteristics of nanosecond pulse LD (with driving circuits) and the synchronization of two nanosecond LD triggers were studied. The results show that the time jitter of nanosecond LD (with driving circuits) is related to the voltage of driving circuits and is in the range of sub-nanoseconds. The time jitter of a single nanosecond LD is 72 ps, when a driving power supply simultaneously triggers two nanoseconds LD in parallel, the time jitter of each nanosecond LD increases to about 200 ps, and the time synchronization of two parallel nanosecond LD is about 300 ps.