In order to explore the influence of temperature impact and cycling on ignition time of laser pyrotechnics，the laser initiators with carbon doped tetraammine bis（5-nitrotetrazolato） cobalt（Ⅲ） perchlorate （BNCP） as primary explosive and fiber-window structure were employed to study performance of BNCP， structure change of laser initiators and structural constraint between fiber and explosive under different temperature alternating experiments （47 h and 94 h）. The experiment results show that the ignition time can reach less than 0.2 ms indicating a great ignition performance before temperature alternating experiment. However， the ignition time delayed more than 0.5 ms after 47 h temperature alternating experiment and some initiators delayed more than 1 ms even misfired after 94 h temperature alternating experiment. The crystal grains of BNCP broke up and the bulk density decreased from 0.43 g·cm^-3 to 0.32 g·cm^-3 after alternating temperature experiment. However， the change of bulk density has no influence on thermal decomposition and ignition performance. The difference of expansion coefficient between ceramic fiber optic components and igniter shell leads to a gap between fiber and doped BNCP during alternating temperature experiment. The gap has a great influence on both laser spot intensity and hot spot diffusion. With structural constraints of fiber and explosive increasing， the ignition gap can decrease effectively during alternating temperature environment and the environment adaptability of laser initiators can be improved.