Image preprocessing system is growing towards high speed, high-resolution, high integration, and high-reliability. Image processing systems are widely applied in military and commercial areas. Subsequently, In the military fields the detection of objects based on image processing technology has become a major research topic its interference immunity and noncontact and concealment objects detection New technology has been enhanced in the world due to the increase in new image processing technology. In the commercial sector, it is widely used in machine vision and industrial detection systems. In general, there are 3 types of image processing systems to implement digital image processing algorithms and each system's main chips are ASIC (Application specific integrated circuit), DSP (Digital Signal Process Chip) and FPGA (Field Programmable Gate Array. In this article, we have designed an FPGA-based image processing system. This system can digitize the data stream from the camera and then digitize it, converting digital signals to analog signals. In recent years, microelectronic technology and large scale integrated circuit manufacturing technology development, specifically FPGA, provide new ideas and methods to improve the performance of the image processing system hence it has more advantages compared to ASIC and it has a great demand in the market. Due to large-amount data and fast-processing speed-required for low-level speed image preprocessing, FPGA based image processing system is well-used in image preprocessing. Results show that FPGA-based image processing is suitable for image preprocessing. System simulation is performed using Xilinx ISE design Suite 14.1. The system is implemented using the Xilinx Spartan-6 XC6SLX45 FPGA with Verilog Hardware Description Language.