Adipose tissue is critical for metabolic homeostasis regulation and the full-play of its function is largely dependent on well differentiation of adipocytes.Perilipin (plin) is a lipid droplets coating protein mainly in adipocyte, and required for optimal lipid storage and fatty acid release.Plin knockout (plin-/-) mice show reduced fat mass with morphologic immaturity.This study was undertaken to determine the effect of plin ablation on adipocyte differentiation.Stromal vascular cells were isolated from fat tissue and differentiated in vitro.plin-/-cells differentiated poorly without pronounced impairment in upstream transcriptional pathway.This attenuation could be partly reversed by exogenous plin expression.Temporal variations of plin-/-cells indicated impediment in lipid droplets maturation during later stages of terminal differentiation.Plin deficiency impaired lipid droplets enlargement and attenuated adipocyte differentiation during later stages.