The invention belongs to the field of airplane fatigue research and relates to the method for assessing and prolonging life of a transparent part of a canopy. The method is characterized by comprising the following steps of 1, determining a typical task profile and flight data parameters of the canopy; 2, computing a temperature and a load of the canopy; 3, charting a temperature / load spectrum of the canopy; 4, performing a ground heating and loading fatigue test on the canopy; 5, computing exposure time of an external field of the canopy and performing an aging test on the external field of the canopy; 6, performing the ground heating and loading fatigue test continuously after aging; 7, making canopy damage tolerance and inspection detailed rules for the external field; 8, performing sound fatigue life analysis on a refueling airplane; 9, giving out service life of the canopy. The method has the advantages that a life assessment and prolongation system of the canopy is established completely, the whole process and method of the life assessment and prolongation of the canopy is included, using safety of the canopy is ensured, and the method is significant and remarkable in economic benefit.