Abstract: Polo-like kinase 1 (PLK1) is a highly conserved serine/threonine protein kinase that has attracted research attention be -cause it plays a critical role in mitosis regulation. PLK1 is overexpressed in 80% of human tumors, which indicates a poor prognosis in most tumors. PLK1 is one of the most promising targets for antitumor therapy because it is upregulated in castrate-resistant prostate can -cer (CRPC). This review focused on the basic structure and function of PLK 1, the relationship between PLK 1 and CRPC occurrence and progression, and CRPC treatment by inhibiting PLK1. This study provides a theoretical basis for the targeted molecular therapy of CRPC.