The invention relates to a hydroelectric power generator with self-protection capability, which comprises a water diversion mechanism and a generating mechanism, and the water diversion mechanism is transmissively connected with the generating mechanism; the water diversion mechanism comprises a water diversion conduit and a water jet pipe, the water diversion conduit communicates with the water jet pipe, and a flow sensor is arranged inside the water diversion conduit; and the generating mechanism comprises a body, a transmission shaft, an angle adjustment assembly and a plurality of blades. In the hydroelectric power generator with self-protection capability, when a rotational speed sensor on the transmission shaft detects that rotational speed is overhigh, the angle adjustment assembly can adjust the angle of the body to control the driving force of water on the blades, so that the rotational speed is controlled, and thereby a protection effect is achieved; moreover, in a working power supply circuit, the current of inputted power is detected by the current limit end of the integrated circuit, so that the current is prevented from being overhigh to burn the integrated circuit, consequently, a protection effect is achieved, and the reliability of the hydroelectric power generator is enhanced.