Abstract:A palynological investigation of 24 samples from the representative Neogene strata of the Xiaolongtan Basin (23°48′N, 103°ll′E) were novelly carried out. Pollen samples were collected from the strata of N1 (clay, sandstone and conglomerate), N2 (clay intercalated with thin bedded lignite at the lower part, and coal bed at the upper part), N3 (marl), and N4 (clay intercalated with thin bedded lignite) in ascending order respectively. Pollen flora was characterized by the predominant appearance of angiospermous elements, representing the parent plants of evergreen broad-leafed types. Variations in the pollen flora were recognized between sample 15 and 16, as more herbaceous pollen of the Compositae types increasing upward in the strata, while certain woody types were minimized or even disappeared, thus dividing the pollen flora into two subzones. According to the current study, the geological age of the flora was suggested to be Middle-Late Miocene (Subzone A) to Early Pliocene (Subzone B), and the inferred vegetational type was evergreen broad-leafed forest, accompanied by a few deciduous elements.