Interference cancellation technology and interference direction finding technology are two typical directions of satellite navigation interference countermeasure, and gradually become the standard function of current satellite navigation equipment. How to realize the efficient integration of interference cancellation and interference direction finding becomes one of the main bottlenecks of engineering application. In this paper, an engineering integration method of GPS anti-jamming and DOA estimation is proposed. By optimizing the noise subspace estimation, the method realizes the efficient integration of high-performance anti-jamming and high-precision interference direction finding. Compared with the anti-jamming module and interference direction finding module, the integration module greatly reduces the engineering resources. The test results show that the method can effectively resist the interference of interference signal ratio 60 dB and provide 2-degree direction finding accuracy.