Folpet is the tradename for the organic compound with the formula C<sub>6</sub>H<sub>4</sub>(CO)<sub>2</sub>NSCCl<sub>3</sub>. It is a fungicide derived from phthalimide (C<sub>6</sub>H<sub>4</sub>(CO)<sub>2</sub>N-) and trichloromethylsulfenyl chloride. The compound is white although commercial samples can appear brownish. It is structurally related to Captan, which is also a trichloromethylsulfenyl-containing fungicide.
folpet resistance is still unheard of due to its multiple effects. However, in 2001 some degree of cross-resistance was reported in iprodione-resistant South African Botrytis cinerea on grape.