Abstract: In order to develop a set of general quality indexes of natural flavors, five parameters closely related to sensory quality of natural flavors including the contents (mass fractions) of moisture, organic solvents, volatile components, carbohydrates and organic acids were selected and the methods to determine their mass fractions were established respectively. Two hundreds and fifty-eight natural tobacco flavor samples were investigated, and relevant data were analyzed using the t-Distributed Stochastic Neighbor Embedding algorithm. The results showed that: 1) The mass fraction distributions of the five chemical indexes in different natural flavors showed apparent characteristics, which could effectively reflect quality differences among the products. 2) The verification results using three common commercially available natural flavor samples showed that the total proportions of the five selected chemical indexes in the natural flavor samples were all above 70%, constituting the majority of the chemical components of common commercially available natural flavors. The five chemical indexes including contents of moisture, organic solvents, volatile components, carbohydrates and organic acids could therefore serve as universal chemical indexes for evaluating the quality and establishing standards for natural tobacco product flavors.