In view of SAR moving target imaging on the sparse scenes, a sparse imaging method is proposed based on 3\|dimensional orthogonal matching pursuit (3D\|OMP) algorithm. In this method, the imaging area is first gridded, and then the 3\|dimensional sparse dictionary matrix is constructed with the 2D motion speed of the moving target being taken as the dynamic parameter, i.e. the parametric sparse representation. In the iteration process, the support set of signals is filtered from calculating the correlation between the echo data matrix and each layer of the 3\|dimensional sparse dictionary matrix. Finally, the sparse representation coefficient on the target scene under the condition of support set is calculated by using the least square criterion. The proposed 3D\|OMP algorithm is an improvement and expansion of the classical OMP algorithm, inherits the advantages of OMP algorithm, such as low computational complexity, obvious signal sparse feature enhancement, and simultaneously has the ability to reconstruct SAR moving target images. The simulation results show that the proposed SAR moving target imaging method is valid.