In the framework of the traditional isotropic total variation (ITV) denoising algorithm, the edge of the image is easily blurred, and it is difficult to maintain the image detail information. Thus, we mainly study the image denoising problem by using L _p pseudo-norm and ITV. The L _p pseudo-norm takes place the L ₁ norm in traditional ITV energy function. Then the energy function is broken into several sub-problems by using alternating direction method of multipliers (ADMM). We treat the differential operator as a convolution operator, then introduce the convolution theorem and the fast Fourier transform (FFT) to further improve the efficiency of the proposed method. Finally, through Matlab, the simulation experiment employs the objective and subjective evaluation methods of image quality for evaluation and analysis. Simulation results show that the proposed method is capable of preserving the edge characteristics of the image and improving the denoising effect efficiently.