Esters of 2-phenylalkanenitriles, such as 3-acetoxy-2-(2-chloro-5- (difluoromethoxy)phenyl)propanenitrile and 3-acetoxy-2-(4-chlorophenyl)propanenitrile, and compositions containing such esters, are useful as fungicides at very low concentrations.Esters de 2-phénylalkanenitriles, du type 3-acétoxy-2-(2-chloro-5- (difluorométhoxy)phényl)propanenitrile et 3-acétoxy-2-(4-chlorophényl)propanenitrile, et compositions les contenant, utiles comme fongicides à de tèrs faibles concentrations.