With the rapid development of GNSS, high precision RTK based on carrier phase is highly valued and widely used in UAV landing, geodetic surveying and mapping. Due to the long distance and low signal power of satellite, it is easy to be affected by interference. The anti-jamming technology of array antenna has good anti-jamming performance, which can effectively solve the problem of weak GNSS signal and easy to be interfered. Based on the analysis of the principle of RTK technology and array antenna anti-jamming technology, the paper summarizes the main factors affecting the carrier phase difference caused by the anti-interference of array antenna, and introduces the specific measures to realize high-precision positioning under the anti-interference condition