The invention relates to a catalyst for synthesizing hexamethylenediamine. The catalyst is composed of three parts, namely a main active ingredient, aids and a carrier subjected to ammoniated treatment, wherein the main active ingredient is Ni or Co; the aids refer to one or more ofmetals such as Fe, Cu, Ru, Re, K, Zn and B or oxides; and the carrier subjected to ammoniated treatment is selected from SiO2 or Al2O3 subjected to ammoniated treatment. In the total weight of the catalyst, the main active ingredient accounts for 1-40%, and the aids account for 0.1-20%. The catalyst disclosed by the invention has the characteristic that the adopted carrier needs special ammoniated treatment. According to the catalyst disclosed by the invention, an ammonolysis reaction of hexanediol or amino hexanol or a hexanediol/amino hexanol mixture is implemented, the hexamethylenediamine product is synthesized under a hydrogen present condition, and the catalyst has high activity, high selectivity and stability.