In the field of cataract, there is such a widespread phenomenon: the majority of patients have complained thatthe second-eye phacoemulsification is often more painful than the first-eye surgery. Recent studies on this phenomenon have found that after cataract surgery in the first eye, in the second-eye aqueous humor there is a high expression of cytokines which is monocyte chemotactic factor-1.It is the focus of the present study to analyze the mechanism of the increase of pain in the second eye with cataract surgery from the molecular level. Monocyte chemotactic factor-1(monocyte chemoattractant protein, MCP-1)which is considered to be a new member of the family of pain,is an important factor resulting in pain, and its specific receptor CCR2 binding exerts its biological activity. This is a review of the inflammatory cytokine research progress on the increase of pain during the second-eye cataract surgery.