To evaluate the imaging quality of a star sensor camera easily and accurately, an image acquisition system for evaluating imaging quality is designed specially. Based on a PCI bus interface, the system takes a FPGA chip as its core control logic and implements the large mass transfer of image data by using a dual SRAM buffer structure. In software, it uses a multithread approach for image displaying and storage and adds in an image evaluating module. So, it can detect the performance of the star sensor camera accurately. Several rigorous test results show that the system can operate stably and reliably and the image data collected are distortionless. When running in the case of 16 bits, the system has its peak image transfer rate up to 40 Mbps.