Abstract: To rationalize leaf sectioning prior to leaf threshing, the cured leaf samples of grade C3F of cv. Hongda were sliced according to Golden section, the near infrared spectra of each section were processed by principal component analysis (PCA) to extract the principal components of near infrared spectra. The sectioning for tobacco leaf was studied by combining with Fisher optimal segmentation method (FOSM), and compared with the existing method in terms of chemical components and sensory quality. The results showed that:1) The sample could be sliced into 11 sections according to Golden section, two principal components were determined via PCA, and their cumulative variance contribution rate was up to 99.789%. 2) Based on the comprehensive score of principal components and combining with FOSM, the optimal sectioning ratio for tobacco leaf of grade C3F of cv. Hongda was determined as base:middle:tip=33%:29%:38%. 3) The contents of total sugar, reducing sugar and nicotine in base, middle and tip differed significantly or extremely significantly, and their sensory scores were 44.87, 47.70 and 49.06, respectively. Meantime, the sensory scores of middle and tip promoted to different degrees comparing with those sectioned with the existing method. It provides a reference for scientific processing and reasonable use of flue-cured tobacco leaves.