The present invention is to provide a process for producing dicyanonorbornane characterized by causing hydrogen cyanide to undergo addition reaction with cyanonorbornene (bicyclo[2.2.1]-5-heptene-2-carbonitrile) in the presence of a zerovalent nickel complex catalyst which is produced by using a phosphite represented by P(x)(y)(z) (wherein P is a phosphorus atom, and x, y and z are each OR, where R represents an aryl group having not more than 18 carbon atoms) as a ligand to reduce a nickel halide with at least one metal selected among zinc, cadmium, beryllium, aluminum, iron and cobalt, wherein the phosphite is one which has a phosphate content of 1.0 weight % or lower based on the whole phosphite.