Abstract: Satellite navigation systems is susceptible to jamming, Space-Time Adaptive Processing (STAP) technique has obvious advantage in the anti-jamming of navigation receiver, i.e. system Degree Of Freedom (DOF) visibly increasing, but traditional STAP would bring serious signal distortion in navigation receiver anti-jamming. In this paper, a novel STAP method based on orthogonal constraint in navigation receiver is proposed. This method modifies the constraint of traditional STAP based on the principle of STAP, avoids the influence of the delay time signal, the jamming is efficiently suppressed by STAP in the acquisition and decoding of navigation signal. Theory analysis and simulation indicate that the novel technique can solve the problem of navigation signal distortion in STAP efficiently.