Abstract: A scattering model based on a multiple expansion is used to solve the scattering problem in this paper.The error between measured scattering data and computed scattering data is considered as an object function.The center position of each thin metallic cylinder is denoted by polar coordinates parameters.The inverse scattering problem is transferred into an optimization problem by minimizing the object function with the polar coordinates parameters being optimization parameters which is solved by pseudo swarm crossover(PSC).A comparison between the multi-phase particle swarm optimization(MPPSO) and PSC is carried out.The results show that PSC has the better convergence and imaging precision,more robust anti-jamming.