According to the requirements of the optimum directional detonating of conventional ammunition, the models of optimum detonating delay time and optimum detonating azimuth were established for single and double scan of the pulse laser circumferential detection system. Matlab is used to simulate the parameters of the model. The influence of detection azimuth, missile-target distance and target pitch angle on the optimum delay time and the detonating azimuth was analyzed. When the laser circumferential detection system scans a target once, the optimal initiation time increase withs the increasing of the missile-target distance, and then increases with the increasing of the azimuth. The change range of the optimal initiating delay is between 0 ms and 20 ms. When the pulse laser circumferential detection system scans target twice, the optimal initiation delay time is 0 ms in most of the time. In the non-zero region, the optimal initiation delay increases with the increasing of missile-target distance.