Terminal area has become a bottleneck restricting the development of civil aviation, and China in the terminal area approach efficiency evaluation still remain in the qualitative analysis stage and lack of quantitative indicators.A circular area with a radius of 100 nautical miles was selected as the study area, and the efficiency of the aircraft was investigated by ADS-B data. The ADS-B data of the approach aircraft were screened by Tianjin Binhai International Airport. The K-means clustering was used to distinguish the aircraft in different approach directions. The efficiency of each direction was calculated and the influence of the entry efficiency was analyzed. It is found that the approach route, the length of the aircraft queue and aircraft type have a significant effect on the efficiency of the aircraft entry, and the impact of the number of takeoff flights on the efficiency of the entry is not significant.