Background　The overactivity of N-methyl-D-aspartate (NMDA) receptors in spinal cord dorsal horn plays a critical role in central sensitization of chronic pain. Recent studies indicate that the phosphorylation of NMDA receptors(NR) are tightly regulated by the Src family tyrosine kinase Fyn, through dynamic interactions with various scaffolding proteins in the NR2B subunit of NR.　Objective　This article aims to further elucidate the mechanism of chronic pain, and explore novel methods for pain management.　Content　The article focuses on the mechanism of phosphorylation of NR mediated by Fyn, and the essential role of Fyn in the central sensitization of chronic pain.　Trend　Prevention of the phosphorylation of NR2B-containing NR mediated by Fyn may become a new target for the treatment of chronic pain.