In this paper, a blue or green laser detection method with large dynamic and energy adaptability is proposed to solve the problem of optical signal acquisition failure caused by the power saturation in short distance and the power shortage in long distance in underwater optical wireless communication links. A gain-controllable detection module consisting of an electronic control liquid crystal light valve, an adjustable gain photomultiplier tube and an FPGA board is added into the underwater wireless optical communication system, which forms a closed-loop control on the communication link in two dimensions of link power and detector gain to ensure that the photomultiplier tube is always working in an optimal state, realizing the underwater long distance, high speed and large dynamic wireless optical communication.