The interconnection network is one of the key elements of distributed computing systems such as MPP (massively parallel processing) or NOWs (network of workstations).In this paper,a high speed optical interconnection data link which has been designed and implemented is presented.Using TDM (time division multiplexing),virtual parallel synchronous data transmission between the PCI buses of two computers has been achieved.The maximum data rate of the link is 1 250 Mbit/s,and the communication distance of link is more than 600 m using multi mode fibers.The design method of the high frequency electrical signals on the network interface card has been analyzed,and the efficient data transmission bandwidth of the link in different transmission modes has been tested and analyzed.