Aimming at the space laser communication system requirement of miniaturization, a scheme of using the avalanche photo diode (APD) type four-quadrant detector to complete the tracking and communication is proposed. This communication system could effectively reduce the volume and power consumption and improve the light energy utilization. The overall scheme of composition and working principle are introduced, the experiment is established in laboratory, and the detection performance which includes data collection, communications rate, limiting sensibility, tracking accuracy is tested. Experimental results show that by use of the APD type InGaAs four-quadrant detector with photosensitive surface diameter of 4 mm, the communication rate is 10 Mb/s, the detection sensitivity is -35.4 dBm and the bit error rate is 10-6 under conditions of Manchester code, intensity modulation/direct detection. The minimum position resolution of the spot position detection is 2 μm, the detecting range of QD is about 0.8 mm, and the angular resolution is 0.8 μrad while the diameter of light spot is about half of the diameter of the photosensitive surface.The feasibility of using the APD type four-quadrant detector for simultaneous tracking and communication is demonstrated, which provides technical support for design of the whole space laser communication system requirement of miniaturization.