Abstract: In order to find novel compounds with high fungicidal activities, a series of acetamido derivatives containing piperidine thiazole moiety were designed and synthesized by the procedure of diazotization, chlorination, cyclization and condensation. Their structures were characterized by ¹H NMR, ¹³C NMR and HRMS. Preliminary bioassay indicated that some title compounds showed good fungicidal activities and the introduction of acetamido group had positive effect on the fungicidal activity. At the concentration of 25 mg/L, compounds 7a , 7c and 7g possessed fungicidal activities against Botrytis cinereal with the inhibition rates of 68.7%, 71.6% and 67.2%, respectively. In addition, compounds 7a , 7g and 7i showed good fungicidal activities against Phytophthora infestans (Mont.) de Bary with the inhibition rate of 50.8%, 61.9% and 55.8%, respectively.