Abstract: This paper discusses the coupling loss induced by pointing error of receiver for coupling space light into single mode fiber in laser satellite communication systems with optical preamplifiers. An approximate analytical expression of burst error rate induced by pointing error is derived and an optimized model for the burst error is established. Given the desired burst error rate and the pointing error of transmitter and receiver, the transmitting beam width, receiving antenna diameter and space optical coupling parameter can be optimized so as to minimize the transmitted power, the power loss induced by pointing error of receiver is also analyzed. The simulation shows that, under the optimal conditions, the power penalty induced by space optical coupling of receiver is less than 2 dB when the product of receiving antenna diameter and the rms pointing error of receiver is less than 0.15 waves.