INTRODUCTION: Caleosins are recognized as the key proteins found in Lipid Droplets (LDs) and are crucial for the creation, maintenance, and breakdown of LDs. Nevertheless, our understanding of caleosins remains limited within Theaceae, a prominent botanical family encompassing economically significant tea and oil tea species. METHODS: In this research, we conducted a comprehensive genome-wide exploration and examination of the caleosin family in Theaceae species with sequenced genomes. The gene number of RESULTS: Caleosins in Theaceae are categorized into either the H-family or the L-family, each exhibiting distinct motif structures and physicochemical properties. Expression analysis revealed an apparent flower-predominant expression pattern of CONCLUSION: This research enhanced our understanding of the lineage-specific evolution of