The invention relates to acetamide compounds and a use thereof, and discloses N-(4-substituted phenethyl) acetamide compounds with a novel structure. A result of in-vitro activity test experiments shows that the compounds have inhibitory activity against cysteine protease (FP-2) and dihydrofolate reductase (DHFR). A result of in-vitro plasmodium killing experiments shows that the compounds have an inhibitory effect on wild and drug-resistant plasmodia.