Abstract: The world is suffering from new crown pneumonia, lack of targeted specific drugs, single treatment methods, which severely affected the treatment of new crown pneumonia. In order to find drugs that can effectively inhibit the spread of new coronary pneumonia, this study uses computer-aided drug design for virtual screening, targeting the 3C protease (3CLpro) of SARS-CoV-2 virus. Chinese and Western medicines with clinically significant antiviral activity and small molecules synthesized in the research group were selected. The molecular docking results show that there are 14 small molecules with a total score greater than 6, of which Sit-144 and Remdesivir score the highest, 8.9413 and 8.0471 respectively. This shows that Sit-144’s anti-SARS-CoV-2 activity may be higher than that of Remdesivir, providing candidate drug support for the treatment of new coronary pneumonia.