Abstract: The array antenna control system uses real-time operation system VxWorks, and the control system computer communicates with the unit antenna through peripheral component interconnect(PCI) device. This paper develops a PCI device driver based on VxWorks real-time operation system. The main tasks finished include the modification of board support package, the initialization of device registers and the design of performance functions. The test proves that the driver is stable and reliable, and can be applied in the control system.