To solve the problems that infrared image of military target has low signal noise ratio and NAS-RIF algorithm is sensitive to noise when applied to restore degraded infrared image,a new modified NAS-RIF blind restoration algorithm based on contourlet transform denoising and image details regularization is proposed. Firstly,the image is preprocessed by contourlet transform denoising. Then,using the optimal threshold segmentation technology,the target′s support reliable domain is extracted. And target edge maintaining constrained item is added in cost function by regularization method to save detail features of the image. Finally,conjugate gradient (CG) algorithm is used to optimize the cost function,which keeps the speed of convergence. Two experiments show that:for aerodynamic infrared degraded image under a low signal noise ratio (SNR) condition,compared to the original NAS-RIF method,the proposed modified algorithm has better recovery effect and the speed of convergence remains almost unchanged.