The invention discloses a method for analyzing and detecting alkaline aroma constituents in tobacco through an ultrasound-assisted cloud-point extraction gas chromatography-mass spectrometry technology. The method includes the steps that 1, a tobacco powder sample is accurately weighed, a sodium hydroxide solution and an internal standard solution are added, soaking and ultrasonic extraction are performed, centrifugation is performed to obtain supernate, a surfactant is added, the mixture is evenly stirred to form a 5%-15% solution, the 5%-15% solution is heated to a temperature higher than the cloud point temperature, and an aqueous phase is removed after standing layering or centrifugal layering; 2, reextraction solvent is added, ultrasonic extraction is performed, a reextraction solvent phase on the upper layer is taken, anhydrous sodium sulfate is added, the mixture is oscillated and then subjected to standing concentration, and the product is filtered through a filtration membrane to obtain a sample to be detected; 3, the sample is detected through a GC-MS, and graph spectrum data are processed to obtain an analysis and test result of the alkaline aroma constituents. The method has the advantages that the pretreatment process is simple, mild and fast, the alkaline aroma constituents in the tobacco can be accurately determined, and the method has great theoretical significance and application value for guiding a scientific formula of cigarettes and improving the aroma and taste quality of the cigarettes.