For the problem of unstable image transmission,this paper designs a real-time video image transmission system based on FPGA,using User Datagram Protocol (UDP) as the communication protocol,the image acquisition is selected from OV5640 image sensor,which integrates the sensor and image processing unit internally,more convenient and stable.The image processing chip is selected from Altera's EP4CE10F17C8N,it is temporarily stored in DDR3 SDRAM,and then the FPGA reads the temporarily stored image information,pre-processes it and then encapsulates the image data in Ethernet frame format,and uses the Gigabit Ethernet chip RTL8211F that comes with the board to send the read information to the PC through Ethernet,and then reads the image information and displays it in real time through the upper computer.The experiment shows that the system achieves real-time video image transmission,and the transmitted image is stable and can work effectively and stably.