Abstract: Puromycin-sensitive aminopeptidase (PSAP) belongs to the M1 family of aminopeptidases, characterized by the N-terminal substrate binding sequence GAMEN, the enzyme activity center HEXXH(X)₁₈E motif, and the C-terminal ERAP-1-like superfamily structural domain. Encoded by the gene NPEPPS located at 17q21.32, PSAP consists of 919 amino acids and is widely distributed throughout the human body, with the highest expression in the brain, followed by the heart and skeletal muscle. It is also found in the liver, renal tubular epithelium, small intestine, large intestine epithelium, and gastric epithelial cells. PSAP primarily relies on its aminopeptidase hydrolytic activity to remove toxic protein aggregates such as Tau, poly Q, and Cu, Zn-superoxide dismutase 1, making it an important factor in the development of diseases such as Alzheimer's disease, Huntington's chorea, and tumors. Existing PSAP inhibitors include bestatin, amastatin, leuhistin, actinonin, and purinomycin, some of which are already available or in clinical trials. This review provides an overview of the structural and biological functions of M1 family aminopeptidases, with a focus on PSAP, to facilitate further research and targeted drug development.