Abstract: Floral morphology of four dominating mangrove species belonging to the two genera, Rhizophoraceae (Bruguiera sexangula, Ceriops tagal and Rhizophora mucronata) and Avicenniaceae (Avicennia marina) from Sundarbans, a world`s largest mangrove swamps have been studied with special reference to their pollination mechanism. In the members of the family Rhizophoraceae, the floral parts are uniformly protected within a comparatively thick and fleshy calyx lobes, a number of filiform appendages present at the apex of the petals and the number of stamens are usually twice as many as the number of petals. The flowers are small, 4-stamens, shortly filamented and minute hairs present on the style; unilocular superior ovary in Avicennia marina. In all the investigated taxa the outcrops mechanism of pollination occur. Pollination agent varied from bird to insect. A basic knowledge of reproductive biology of a plant in important towards cope up a meaningful conservation strategy.