Abstract: In order to clarify the relationship between grouping and grading factors, chemical or sensory quality factors of flue-cured tobacco, 588 primary flue-cured tobacco samples from three leaf positions in six years were analyzed for canonical correlation. The results showed that three pairs of extremely significant canonicals were extracted between the appearance quality and chemistry or sensory quality, and the appearance quality canonicals reflected 29.2% or 25.7% of the total variations of chemical or sensory quality respectively. Among them, the factors that had the greatest impact on chemical quality were the leaf position and leaf structure, followed by color, then body and oil. The factors that had the greatest influence on sensory quality were color and maturity, followed by leaf position and leaf structure, then body. Leaf position was the most important factor to interpret the variation of chemical quality. Color and maturity were the most important factors in explaining the variation of sensory quality. The canonical correlation analysis based on quality indicators can provide data supporting the rationality of existing flue-cured tobacco grading standards.