For the need of high-speed image processing, a mixed PCI Express switch board is presented. According to the electrical characteristics of high-speed serial communication and the CPCIE system specifications, the PCIE lanes and high speed serial image signals were transferred to the down stream slot in a group following the CPCIE switch rules. This system could advance the PCI express links and switch the optical fiber images real-timely with a single board, provided flexible access of serial fiber images in the case of ensuring high-speed PCI Express bandwidth available. Compared with the traditional system, this system has fewer cables and higher speed. The board has been used in practice.