Avalanche photodiode single-photon detector is one of the ultra-sensitivity photoelectric detector, which has important applications in the fields of long-distance laser ranging, laser imaging, and quantum communication. However, due to the high temperature sensitivity of the avalanche voltage, the avalanche photodiode single-photon detector is prone to fluctuation of the avalanche gain when it works in the field environment, which leads to the delay drift and seriously reduces the time stability. In this paper, we proposed a method of stabilizing the delay of the single-photon detector. An embedded system was used to control avalanche photodiode at constant low temperature and compensate the delay drift of the detection circuit caused by the change of environment temperature in real time. A high time stability avalanche photodiode single-photon detector was realized by this method. In the experiment, the environment temperature changed from 16 ℃ to 36 ℃, and the avalanche photodiode was controlled at 15 ℃. After compensation, the delay drift of the avalanche photodiode single-photon detector was within ±1 ps, and the time deviation was 0.15 ps@100 s. This work is expected to provide an effective solution for the application of high-stability single-photon detector in the field and space environment.