Abstract: Ten new α-methylthiocyclododecanone oxime ether were synthesized by the reaction of alkylation of α-methylthiocyclododecanone oxime as intermediate with alkyl halides, which were prepared from α-methylthiocyclododecanone oxime and cyclododecanone as starting material. Their structures were confirmed by elemental analysis, 1H NMR, 13C NMR and IR spectra. The preliminary bioassay results showed that some of compounds have good fungicidal activities against Rhizoctonia solani, Fulvia fulva(cooke)cifer and Botrytis cinerea. The EC50 values of F3 and F8 against R. solani and F. fulvia were 11.22 and 13.38 μg/mL, 37.12 and 48.41 μg/mL, and EC50 value of F9 against B. cinerea was 17.96 μg/mL, respectively.