This paper reports studies on the microsporogenesis,megasporogenesis and em-bryo sac development of Ananas comosus(L.)Merr.The cytokinesis of the microspore mothercell in meiosis was of the successive type.The arrangement of microspores in the tetrads waszygomorphic or decuassate.The anatropous ovule was bitegminous and crassinucellate.Themegaspore mother cell gave rise to a linear tetra.The chalazal megaspore became a func-tional megaspore.The development of the embryo sac conformed the Polygonum type.