Abstract: PCGF3（polycomb group ring ginger 3） as a homologous of the PCGF1-6 and a major component of the PCGF3-PRC1 complex, has a specific genomic localization and catalytic activity. PCGF3 mediates epigenetic histone modifications and maintains transcriptional inhibition of many genes, including Hox gene, throughout organic development. Previous studies have found that PCGF3 is related to the drug efficacy, diagnosis, and progression of multiple diseases. This review first introduces the structure of PCGF3 and its complex, then expounds the influence and possible mechanisms of PCGF3 on chromosome structure, X chromosome silencing and gene transcription. Furthermore, the related research progress of PCGF3 functions in diseases is introduced in this review.