As an important agricultural product, cigar tobacco lacks reports on chemical compositions. The investigation on characteristic components of Yunnan local cigar tobacco revealed 15 Cembrane-type diterpenes including nine undescribed ones (1–9). Their structures were elucidated on the basis of extensive spectroscopic analysis, computational calculations, and X-ray diffraction. The skeleton of Cigarcembrane (1) with a new 6/12-ring system was previously undescribed. This is the first time to report eunicellane (2–7) and gersemiane (8–9) skeletons from plant resources. The transformation mechanism of cigarcembrane, eunicellane, and gersemiane from Cembrane during cigar fermentation was postulated. Chromatographic analysis revealed 10 as a marker for cigars. All the isolated compounds showed the promotion of hOMF cell proliferation, enlightening us to seek lead compounds in mouth care.