Abstract: Aiming at the necessity of fuze getting distance and azimuth information of the target in the short range(greater than 10 m) when underwater target warhead interaction, in order to take full advantage of transmission laser energy, increase the laser echo power, did optimization design on angle parameters of single-beam pulsed laser orientation recognition underwater system. The echo power equation of underwater target detected by pulsed laser orientation recognition system was derived, the relationship between the echo power and the angle parameters was built, the angle conditions and the expression of perfusion area's distance were got. Based on the multi-island genetic algorithm, the angle parameters were calculated by iSIGHT software. The results show that when the angle between the emitting beam center and the axis is 30, the angle between the receiving field of view center and the axis is 34.5, and the field angle take 10 can obtain the minimum perfusion area's distance in the case without consider other factors. Thus, this work can provide a theoretical basis for designing the angle parameters of single-beam pulsed laser orientation recognition underwater system.