Abstract: For the problem of associating the 1D scattering centers at unknown viewing angles existed in the technique of non-cooperative radar target 3D reconstruction, a method of scattering centers association based on geometric constraint is proposed. In the method, a part of reliable scattering centers are automatically selected and effectively associated via checking the back-projection error. Meanwhile, with the motion parameters estimated from the range data of the associated scattering centers, more scattering centers on the target can be associated and reconstructed. The simulations verify that, the proposed algorithm is applicable to the complex situations where missing, fault and overlapping points existed in the 1D scattering centers, and the robustness of the scattering centers association and reconstruction for unknown moving target can be effectively enhanced.