RNA m6A methylation is the most common type of RNA modification, and RBM15 regulates various cellular processes by writing m6A methylation on RNA. m6A methylation mediated by RBM15 significantly affects RNA stability and translational efficiency, thereby regulating gene expression. In-depth studies have revealed that RBM15 affects the progression of various diseases by regulating the expression of multiple genes, and its m6A methylation modification process is also considered to be an effective therapeutic target. In this paper, we review the latest research progress on the regulation of m6A methylation modification of RBM15, its molecular regulation in various diseases, such as cancer and metabolic diseases, and the potential therapeutic drugs derived from it, with a view to providing therapeutic strategies for the subsequent research on RBM15 and gene therapy targeting RBM15.