An experimental statistical design was used to determine cyanide concentration and time optima for the induction of formamide hydrolyase enzyme in a strain of Fusarium oxysporum isolated from a cyanide-containing industrial effluent. Fourteen experiments (including replicates) were carried out within an experimental domain with a cyanide concentration between 0 and 2 mM and induction time varying between 1 and 17 h. A cyanide concentration between 1.0 and 1.9 mM and an induction time between 12 and 18 h were optimal for formamide hydrolyase induction in biomass with 5 days of growth.