3CLpro is the main protease of the novel coronavirus (SARS-CoV-2) responsible for their intracellular duplication. Based on virtual screening technology, we found 23 approved clinical drugs such as Carfilzomib, Saquinavir, Thymopentin and etc., which showed high affinity with the 3CLpro active sites. These findings suggest that 3CLpro inhibitors might be potential candidates for further activity detection and molecular modification.