This document describes the instructions for use and expected applications of the rat urokinase-type plasminogen activator receptor (uPAR; CD87) enzyme-linked immunosorbent assay (ELISA) kit produced by Uscn Life Science Inc. Wuhan. The kit is intended for in vitro research use and quantitatively measures the uPAR content in rat serum, plasma, cell culture supernatant, or other related biological fluids.