Abstract: The antifungal activity of 2-(benzylsulfonyl)-5-(2,4-dichlorophenyl)-1,3,4-oxadiazole ( 2008334 ) against Fusarium oxysporum was preliminary evaluated with the method of mycelial growth rate in vitro.The results showed that the EC50 value of compound- 2008334 was 27.54 μ g/mL,which was similar with that of hymexazol (29. 13 μ g/mL).The spore germination of F.oxysporum can be inhibited by compound- 2008334 with EC50 value as 41.37 μ g/mL.After treated by 2008334 at 100 μ g/mL,the permeability of the cell membrane increased significantly,and the contents of reducing sugar and soluble protein in mycelia increased for a short time,and decreased subsequently.