The invention provides a Retinex image enhancing method and a Retinex image enhancing system. The Retinex image enhancing method comprises the steps of: carrying out repeated average filtering iteration on a video source image acquired by a video camera to generate an image illuminance component; acquiring an image reflection component according to the source image and the image illuminance component; correcting the image illuminance component and the image reflection component; and calculating to obtain an image after Retinex image enhancement according to the corrected image illuminance component and the corrected image reflection component. The Retinex image enhancing system comprises an iterative convolution module, a reflection component generation module, an illuminance component correction module, a reflection component correction module and an enhanced image generation module, wherein the modules are implemented on an FPGA. The Retinex image enhancing method and the Retinex image enhancing system can be used for carrying out self-adaptive enhancement on images of different types, and ensure the real-time performance of image enhancement.