To address the problem of limited luminance dynamic range in stage scenes， this study proposes a method for low-light enhancement of the stage based on an improved Retinex algorithm. First， the low-light image of the stage scene is enhanced using the improved Retinex algorithm to obtain an overall enhanced image. Then， the original image is fused with the enhanced image， and background areas that are over-enhanced and do not need to be enhanced are processed to obtain the final image. The improved Retinex algorithm uses a Gauss-Laplace high-pass filter to find the reflected and illumination components， thus addressing the problem of detail loss in the reflection component. It then performs contrast and detail enhancement on the reflected component and multiplies it with the light component to produce the enhanced image. This method performs field-programable gate array （FPGA） hardware platform verification based on software platform verification. The experimental results show that， compared with other classical methods， this method yields a noticeable visual improvement， with an average increase of 57.06% in peak signal-to-noise ratio （PSNR） and 27.34% in structural similarity （SSIM） in different stage scenes. This improvement is particularly significant in stage scenes with substantial differences in brightness between light and dark areas. The images processed by this method restore the true luminance dynamic range of the stage and exhibit good natural color saturation without distortion， ensuring better image quality.