Meteorological factors are significant to aviation flight. To investigate the fuel efficiency in aviation flight, base of aircraft data (BADA) model was combined with meteorological factors, and the aircraft fuel consumption correction model was built. Taking the example of one inbound flight approach at Guangzhou Baiyun Airport, the flight simulation tests were developed and the influence of the change in air temperature, air pressure and wind speed on aircraft fuel efficiency was discussed from two aspects:fuel flow and fuel consumption. The results show that the correlation between meteorological factors and fuel efficiency is obvious. When aircraft flight altitude is certain, if air temperature rises, fuel flow and fuel consumption increase, and fuel efficiency decreases; if air pressure rises, fuel flow changes little but fuel consumption slightly decreases, and fuel efficiency increases; if wind speed rises, fuel flow and fuel consumption firstly decrease and then increase, fuel efficiency increases first and decreases afterwards, and fuel efficiency is the highest when wind speed is 4 m/s. If flight altitude reduces, air temperature and air pressure increase but wind speed increases, fuel flow increases with a slight fluctuation, and fuel efficiency decreases. Fuel consumption in approach can be reduced by about 3% under the best meteorological factors. The study results are significant for improving the fuel efficiency in actual flight.