Rosai-Dorfman disease (RDD) is a rare histiocytosis typically with bilateral painless cervical lymphadenopathy. Laboratory data are nonspecific, and the presence of emperipolesis in large foamy S-100+ CD1a- histiocytes is the prominent histologic feature. The pathogenesis of RDD still remains elusive. According to published studies, we propose that RDD cells might represent intermediate recruiting monocytes with differentiation blockade. Both disturbance of homoeostasis and inherent genomic alterations could contribute to initiation of the disorder through signal transduction. Several inflammatory molecules such as macrophage colony-stimulating factor, IL-1β, IL-6, and tumor necrosis factor-α also play a pivotal role in the development of this rare entity. Additional studies are needed to further elucidate the essence of the disease.