Mpro of Severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2 Mpro, also referred to as SARS-CoV-2 Main protease, SARS-CoV-2 3CL protease) plays an essential role in viral replication by processing the polyproteins 1ab at 11 cleavage sites. Inhibiting the activity of this enzyme would block viral replication, making it a promising target for anti-coronaviral therapeutic agents. The assay is fast and convenient and requires just two steps. In the first step, the Mpro enzyme is preincubated with the compound for 30 minutes. The reaction is initiated by adding substrate solution at the second step. Fluorescent intensity is measured with a fluorescent plate reader at the excitation wavelengths of 340-360 nm and emission wavelengths of 460-480 nm.