The invention discloses a method for detecting the yellowing degree of flue-cured tobacco leaves during a curing process. The method is characterized in that representative tobacco leaves are selected and put in a sampling window during the process of curing and loading flue-cured tobacco leaves; when the yellowing degree of the tobacco leaves needs to be judged at a key temperature point of a tobacco leaf yellowing stage, 5-15 representative tobacco leaves are taken from the sampling window, and the average value of leaf chlorophyll content (namely an SPAD (Soil and Plant Analyzer Development) value) is determined by a chlorophyll meter; and main detection stages include 40 percent of yellowing, 50-60 percent of yellowing, 70-80 percent of yellowing and 90-100 percent of yellowing. The method fills in the blank of specific indexes and specific determination methods for the yellowing degree of flue-cured tobacco leaves during the curing process; the method is clear in index, has objective judgment indexes, can quantize the curing process and reduce the loss caused by visual errors, and is easy to operate and grasp; and the method is used for monitoring the flue-cured tobacco leaves and can ensure that the flue-cured tobacco leaves are uniform in color and good in chromaticity, so that the comprehensive quality and the curing quality of the tobacco leaves can be improved. Therefore, the method is suitable for tobacco leaf curing enterprises.