Accurate calculation of pollution emission for aircraft engines is the foundation of pollution control and environmental evaluation. the traditional and conservative method is using ICAO reference data or simulating data by flight dynamic model to have the flight parametes, so as to estimate the emission data. as the estimation is different from the actual data, the calculated emisssion data will not accurately reflect the specific emissions. this paper gives the method the calc ulate the emission based on the QAR recorded data. firstly, compute the accurate and credible flight data by using the interpolator sharing method, the kalman filter algorithm and weighted algorithm. then, with the reference of ICAO emission model, a corrected method is given on the basic of temperature, humidity, altitude, indicated airspeed and fuel flow. thus we can get he actual emission data is calculatedby DELPHI program for B737-700 flying from chong-qie airport to shanghai airport. the result is compared with ICAO reference data in the same condition, and than the change of pollutant emissions in different flight phases is analyzed.