The Rajasthan basins (Bikaner-Nagaur, Barmer and Jaisalmer) are rich in diverse plant megafossils within the Palaeogene (Palaeocene–Eocene) sedimentary sequence. It is critical to investigate the past plant biodiversity preserved as fossils in the Rajasthan basins to understand its palaeomegafloristic composition, palaeoclimatic interpretation and biogeographic patterns. Here, we present a summary of plant diversity records documenting Palaeogene floristic, climatic changes and biogeographic trends. We accomplish this by assembling published records of megafossil plant remains, because these offer better spatial and chronological resolution than the palynological data. The presence of significant angiosperm elements typical of the Gondwana continents make the flora fascinating. Analyses of the Rajasthan floral assemblages based on the distribution of the nearest living relative taxa suggest that tropical warm and humid climatic conditions prevailed at the depositional time. An analysis of the Rajasthan floras indicates that the Palaeogene floral assemblages consist of mainly evergreen forest elements followed by a few deciduous elements in contrast to the xeric and mostly deciduous vegetation in the area. This change in the vegetation pattern must reflect a climatic change and seems to indicate an increase in rainfall seasonality. The present review aids in our comprehension of the palaeoenvironmental circumstances that led to the occurrence and evolution of plant diversity in the Rajasthan basins across the Palaeogene.