The present palynological investigation of Bignoniaceae in India highlights the presence of heteropolarity, multi-orate colpi, dimorphism & polymorphism among the members. These palynological characters are not common among the dicots and studies on them are quite meagre. So, the present study has been undertaken to explore more of them as they are significant in taxonomic deductions, in recognizing several taxons & also throws light on the evolutionary relationships. The freshly collected polleniferous material of 13 species of Bignoniaceae, belonging to 12 genera, from West Bengal were acetolysed & thoroughly investigated using bright field light microscopy and their respective photographs were taken. The surface pattern of the pollen grains is mostly reticulate & few are psilate. The apertural pattern ranges from inaperturate to tri-tetrazonocolpate to tri-zonocolpor (oid) ate to hexazonocolpate, thereby exhibiting a high degree of eurypalyny in the taxon. Multi-orate colpi are observed in Fernandoa adenophylla, Jacaranda obtusifolia, Markhamia lutea, Parmentiera cereifera, Tabebuia heterophylla and Tabebuia aurea. Polymorphic pollen (Parmentiera cereifera & Pyrostegia venusta), dimorphic pollen (Oroxylum indicum) & heteropolarity (Pyrostegia venusta) has been observed in the family. Pollen grains of Fernandoa adenophylla, Jacaranda obtusifolia, Mansoa alliaceae and Tabebuia heterophylla has been investigated for the first time in the present study. Heteropolarity in Pyrostegia venusta, multi-orate colpate pollen grains in Fernandoa adenophylla, Jacaranda obtusifolia, Markhamia lutea, Parmentiera cereifera, Tabebuia heterophylla, Tabebuia aurea & polymorphism in Parmentiera cereifera & Pyrostegia venusta has been surfaced for the first time in the present study. Few suggestions are made regarding the significance and evolutionary trend of the multi-orate features of the pollen grains. The presence of both types of grain in Parmentiera cereifera, i.e. a) pancolpate apertural pattern, lacking ora and b) pancolpate with multi-orate features, indicates that the latter might have evolved from the previous one.