The invention relates to a semiconductor avalanche photoelectric detector using a low dimensional quantum dot multiplication layer. In the multiplication layer of the semiconductor avalanche photoelectric detector, there are several quantum dot layers which have a narrower band gap than the multiplication layer and form an I-type band structure with the multiplication layer materials. With the detector provided by the invention, the gain coefficient increases obviously; excess noise can be suppressed; and it can be widely used to enhance the performance of the avalanche detector in different bands such as Si-Ge, GaAs-InAs, InP-InGaAs, InAlAs-InGaAs, and GaAs-AlSb, and raise the application level of avalanche detector systems including high speed optical communication, single photon counting, laser radar, quantum information and etc.