The pollen morphology of five species of Dillenia and Schumacheria of Dillenioid clade (Dilleniaceae) dis-tributed in the Western province of Sri Lanka was inves-tigated using light and scanning electron microscopes. Dillenia indica L., Dillenia retusa Thunb., Dillenia suf-fruticosa (Griff. ex Hook.f. & Thomson) Martelli, Dillenia triquetra (Rottb.) Gilg and Schumacheria castaneifolia Vahl were the species studied for pollen morphology and its bearing on species identification. The pollen grains of the species studied are all monads, radially symmetrical, isopolar and sub-oblate to oblate-spheroidal, with tri- or tetracolpate apertures. Exine sculpture is punctuate but for Dillenia retusa, which exhibits reticulate pattern. The polar axes of the pollen grains ranged from 13.6-22.2 µm and the equatorial axes from 14.8-27.1 µm. The polar and equatorial diameters and mesocolpium length are found to be useful for segregating the species studied, and despite the pollen heteromorphy.