Abstract: In this paper, a 3-D imaging technique for interferometric inverse synthetic aperture radar is presented. And the criteria of determing and the angle glint in interferometric angle measurement are given. Furthermore, the 3-D imaging technique under two tracking systems is analyzed. This technique can effectively overcome the random phase dithering caused by tracking error under the continuous tracking system and satisfactorily solve the alignment of the different focuses of ISAR images under the step tracking system.