Regarding the problems of difficult manual detection of slope and incomplete measurement data in the construction of high and steep slope sparing，an automatic detection method of airborne slope cutting quality is proposed.Firstly，the equation of the motion trajectory of the excavator tooth tip coordinates is established based on the Beidou positioning point，and the wear error of the excavator is corrected.Then the relationship between the spatial coordinate trajectory of the excavator's tooth tip and the slope characteristics is analyzed.Through the study of the recognition and acquisition algorithm of bucket tooth tip coordinate data，the purpose of indirectly expressing the slope quality by using the tooth coordinate is realized.The practice of engineering application proves that this method meets the requirements of slope cutting quality inspection accuracy，replaces manual measurement，and improves construction efficiency.