For research at home and abroad, and to ensure the accuracy and real-time of the acquired images, to achieve the function of moving target detection, a digital image processing application based on FPGA - moving object detection is proposed, and the image acquisition and image processing two parts are studied, the image acquisition is OMINIVISION OV5640 image sensor, which comes with an embedded microprocessor to support image scaling and translation. By the programmable device FPGA to receive and send data to the FPGA external large-capacity SDRAM memory for storage, image processing is selected Intel Cyclone IV series FPGA chip, for the image acquisition process of a variety of random noise, through the verilog HDL hardware description language written RTL register transmission level code, to achieve image acquisition and storage, average filtering, expansion algorithm, corrosion algorithm, morphological operation closed calculation design The processed image is used for moving target detection and VGA display display. The system is mainly composed of camera acquisition module, SDRAM controller module, display driver module, image processing module, through design simulation, the results show that the system realizes real-time acquisition and processing of digital images, reaching 640*480 resolution display of 30 frames per second.