The invention discloses a nicotine converted tobacco plant color quality rapid screening method based on incubation treatment. The method comprises the steps of seedling sampling, alkaloid extraction,sample incubation, instrument analysis and data analysis. The tobacco leaves are hatched and cultured without needing to add an activator and control the humidity, and a tobacco seedling and tobaccoleaf sample is placed in a closed container to be incubated for 10-12 hours, so that the alkaloid extraction and analysis can be carried out. According to the experiment, the humidity of the incubation reaction does not need to be additionally controlled, and the activator does not need to be added, so that the reaction condition is simplified, the incubation reaction can be carried out in any temperature-controllable environment, the incubation time is greatly shortened, and the working efficiency is improved. According to the invention, thealkaloid content analysis is carried out by using agas chromatograph-mass spectrometer, and the contents of nicotine and nornicotine can be determined within 5-6 minutes, so that a PNC value is obtained, and the analysis time of a sample solution is shortened. According to the invention, the PPNC is introduced as a simplified scheme of the PNC, is easier to obtain than the PNC and is not influenced by the factors, such as standard substance purity, standard curve quality, etc.