Abstract:Very long baseline interferometry(VLBI) plays an important role in China’s Lunar Exploration Program(CLEP). In order to obtain the accurate positioning of the lunar probe, achieve the accurate orbit determination function and complete the orbit correction during the flight of the probe, it is necessary to use the VLBI station to observe the lunar probe in real time. In this paper, we mainly use the arithmetic mean(AM) and standard deviation(STD) as precision evaluation indexes. We analyze the VLBI measured data of Chang’e-4 probe, relay satellite and Chang’e-5 probe from Shanghai Observatory for the data stability of the total observation period. Based on the simultaneous observation of the S and X bands of Chang’e-4, we emphasize the quality analysis of the data of different frequencies. We carry out time delay, time delay rate measurement error and check residual analysis for each working section of the detector, and the correlation between the motion of the detector and the data change. The results show that Chang’e-4 has the highest accuracy of 1ns among the three types of probes. Chang’e-5 probe has better observation stability than the other two types of detectors. Different ground stations have different observation accuracy of the detector, and the measured data show different characteristics in different working stages of the detector.