In the application of airbone single-observer passive wireless radio frequency injection location, if there has outliers in the observed value, the application of the EKF algorithm will make the location estimation biased. Therefore, a robust EKF algorithm is applied to airborne single-observer passive wireless radio frequency injection location system. Firstly, airbone single-observer passive bearing location model is build, and the robust equivalent weight matrix built by standardized observation residuals is used to resist outliers. Then, in order to improve the efficiency of passive location system, the robust EKF based on chi-square test is proposed by creating a chi-square statistical model. It can distinguish outliers through chi-square test, and then call the robust EKF to complete location solution. Through rejecting single outlier and continuing outliers to test the ability of the algorithm. Simulation result shows that the suggested algorithm has great outlier suppression ability and the robust EKF based on chi-square test is fast.