Under dark vision conditions,the images captured by image acquisition equipment have low visibility.Retinex model enhancement method can map the corresponding reflective image by manipulating the estimated illumination.However,since the noise term is not in consideration,it is prone to amplify the noise of the enhancement results.To solve this problem,an image enhancement algorithm based on nonconvex constraint and noise suppression is proposed.Firstly,a new Retinex model with the noise term is defined.Then,an objective function with l0 regularization constraints is constructed based on the smoothing filter with gradient minimization,so as to obtain illumination images.Then,based on the above procedures,an objective function with l1 regularization constraints is established to separate the noise from the reflective image.Finally,after image reconstruction,the final enhancement results are obtained.The experimental results show that the proposed algorithm not only improves the visual effects of the image,but also has stronger noise suppression ability while retaining more information of the image.