The retinal pigment epithelium(RPE)is a pigmented simplecuboidal monolayer of epithelial cells that located between the photoreceptors in the neural retina and the Bruch's membrane in the vascular choroid and is critical for the survival and function of retinal photoreceptors. The pathogenesis of multiple congenital RPE diseases is closely related to embryonic development. This review summarized the current knowledge of the molecular mechanisms controlling early steps of RPE development, with emphasis on basic process, critical signaling molecules, key transcription factors and pathway maintaining the RPE cell fate.