Using TBD to reduce the minimum detectable SNR can be used to detect weak targets of pulsed laser radar sensor. Firstly, the pretreatment measures are given to enhance the single frame SNR. Especially, with the width characteristic of laser target under high sampling rate, the down-sampling method is introduced, which can not only eliminate a large number of single-point noises, but also can solve the acquisition problem of relatively stationary or low-speed targets. Then the TBD algorithm based on HT is proposed. Finally, the experiments indicate that the algorithm has good detection performance and can detect single and multiple targets.