Abstract: A new target location algorithm based on Gauss-Newton iterative algorithm for complex bistatic radar systems is developed.In the improved algorithm,all the observational data are adopted to compose a nonlinear least square equation,the location estimation resolved by a measurement subset which has higher accuracy among all subsets is utilized as an initialized value,which is close to the truth value.The iterative method of the variable step size is introduced,and the specific steps are given.Simulation shows the algorithm improves the accuracy of target location and ensures iterative convergence.