To obtain the composition containing 2-thiocyanopyridine-1-oxide and one or more kinds selected from compounds known as antifungal agents, antiseptic agents, and/or antibacterial or bacteriostatic agents, and exhibiting extremely remarkable synergistic effects.

This composition contains 2-thiocyanopyridine-1-oxide and one or more kinds selected from the group consisting of 3,3,4,4 tetrachlorotetrahydrothiophene-1,1-dioxide, 2,2-dibromo-2-nitroethanol, 1,4-bis(bromoacetoxy)-2-butene, dichloroglyoxime, dimethyldithiocarbamate sodium salt, distribromomethylsulfone, N-benzyl-2,3,-dichloromaleimide, methylenebisisothiocyanate, 4,5-dichloro-1,2-dithiol-3-one, 2,2-dibromo-3- nitrilopropionamide and other 16 compounds. The composition exhibits the antibacterial effect in the reduced amount of use and also that effect can be maintained.