Abstract: The model of bistatic inverse synthetic aperture radar(ISAR) is analyzed in wave-number domain.The characteristic of the bistatic ISAR is represented with two parameters,the bistatic angle and the azimuth angle of equivalent line of sight(LOS),affecting the modul and direction of the radial wave-number respectively.The observation region is partitioned into different parts using the bistatic angle isoline.Then the variation of bistatic angle and azimuth angle of equivalent LOS is discussed in each part to determine corresponding bistatic ISAR imagery algorithm.Finally,some simulation results are given to prove the correctness of the analysis.