Provided are a method of analyzing ubiquitin-proteasome activity with respect to a target polypeptide and a method of screening a ubiquitin-proteasome inhibitor. According to the provided methods, the pattern of lysis of a target polypeptide by a ubiquitin-proteasome in target cells may be quantitatively analyzed in a rapid and highly sensitive way, a ubiquitin-proteasome inhibitor may be screened in a rapid and highly sensitive way, and an anticancer agent and the activity thereof may be rapidly screened.