The invention discloses a method for improving receiving signal imitation accuracy based on a base-band equivalent channel model. In a wireless communication system, an emitting end digital base band signal is converted into to a receiving end digital base band signal through the processes of digital up conversion, DA conversion, a radio frequency emitting passage, an emitting antenna, a wireless channel, a receiving antenna, a radio frequency receiving passage, AD conversion and digital down conversion. The whole process can be regarded that the emitting end digital base band signal is distortedthrough a channel, and finally the receiving end obtains the distorted digital base band signal, the channel is also named as a base band equivalent channel. Through the modeling of the base band equivalent channel, the accuracy of the receiving signal imitation is improved, the performance of a demodulation algorithm selected by the system to an actual receiving signal is guaranteed. The method can be applied to the link level simulation in a regeneration forwarding system and a transparent forwarding system in a satellite communication.