The traditional BDS diversity receiver uses the satellite signal of each antenna for positioning directly, resulting in unclear positioning position points and low positioning accuracy. To solve this problem, a high-precision diversity positioning technology is proposed. Firstly, an antenna delay calibration algorithm based on channel code phase is proposed to eliminate the hardware delay difference of different antennas. Then, a method of calculating antenna baseline vector in Beidou coordinate system independent of external attitude information is introduced, and the calculation accuracy is theoretically analyzed. Finally, a diversity positioning algorithm considering antenna delay and baseline vector is introduced. By reducing the positioning results to the reference antenna, the positioning position points are defined, thus improving the positioning accuracy. The comparison test was carried out under outdoor static environmental conditions. The results show that the positioning accuracy of BDS diversity receiver is significantly improved by this positioning technology, and the positioning accuracy of single antenna is achieved.