NonGaussian impulsive noises widely exist in real world, which seriously impacts on the performance of the adaptive filtering algorithms based on l2 norm optimization criterion. In various types of adaptive filtering algorithms, the affine projection sign algorithm (APSA) combines the good convergence feature of the affine projection algorithm (APA) and the suppression capability of the sign algorithm (SA) for nonGaussian impulsive noises. Thus, it has good performance in nonGaussian impulsive noise conditions. However, the step size of APSA is fixed and does not consider the system sparsity, so that there are certain limitation in parameter selection and convergence speed. Therefore, in this paper, the variable stepsize method and proportion matrix thought are combined together, the step size function is introduced, and a robust affine projection sign adaptive filtering algorithm  the variable stepsize improved proportion affine projection sign algorithm (VSSIPAPSA) is proposed, which can not only alleviate the contradiction between convergence speed and steadystate misadjustment, but also increase the adaptability of the system to different sparsity and noise characteristics. Theoretical analysis and simulation results demonstrate the effectiveness and robustness of the algorithm.