Abstract:In present paper, pollen morphology of seven species of the genus Tongoloa from China was studied. They are concentrated in the Hengduan Mountains and some species extend to nearby area.The pollen grains were examined under LM and SEM. The result shows: They are rhomboidal types except T. dunnii (Boissieu) H. Wolffand T. silaifolia (Boissieu) H. Wolff which are rectangular type. All the pollen grains are not original or typical rhomboidal types. T. gracilis H. Wolff, T. elata H. Wolff are presented various shapes i.e. subrhomboidal. subelliptical and subrectangular. This is a differential rhomboidal type. So we may consider that the evolutionary trends of pollen types were from rhomboidal type to rectangular type in the genus Tongoloa H. Wolff. In our earlier paper we touched similar pollen morphology in the genus Physospermopsis H. Wolff. The pollen information suggest that Tongoloa H. Wolff may be closely related to the genus Physospermopsis.