Background: Raffinose synthase (RFS) plays a crucial role in plant growth and development, as well as in responses to biotic and abiotic stresses. However, its functions in Brassica napus remain poorly understood. Methods: To investigate the characteristics of the RFS gene family in B. napus (rapeseed), five Arabidopsis thaliana RFS gene sequences were used as references to identify thirteen RFS genes in B. napus, four in Brassica rapa, and six in Brassica oleracea. A comprehensive analysis was conducted, including molecular characteristics, phylogenetic relationships, conserved protein motifs...