NOVELTY - Producing a N-substituted amine compound (Q), comprises (a) reacting a first amine with an alcohol or with a second amine in the presence of a composite metal oxide catalyst, where the: oxide catalyst is copper(II) oxide-nickel(II) oxide (NiO)-iron(II,III) oxide (Fe3O4), NiO-Fe3O4, CuO-Fe3O4 or CuO-NiO; the first amine and the second amine are the same or different and independently (A) an aliphatic amine compound (ia) or (B) an aromatic amine compound (ib) and (ib1) to (ib8); and the alcohol is (C) an aliphatic alcohol compound (ic), or (D) an aromatic alcohol compound (id1) to (id7).    USE - The method is useful for producing (Q) (claimed), which is useful as chemical intermediate in the production of dyes, synthetic resins, medicines, and pesticides.    ADVANTAGE - The method produces the N-substituted amine compound: with high yield, efficiency, conversion rate and selectivity and ease for recovery; without any medium; and using the catalyst made of cheap nonnoble metals, which is non-caustic, environmental friendly and easy to be separated and reused.    DETAILED DESCRIPTION - Producing a N-substituted amine compound (Q), comprises (a) reacting a first amine with an alcohol or with a second amine in the presence of a composite metal oxide catalyst. The composite metal oxide catalyst is copper(II) oxide-nickel(II) oxide (NiO)-iron(II,III) oxide (Fe3O4), NiO-Fe3O4, CuO-Fe3O4 or CuO-NiO. The first amine and the second amine are the same or different and independently (A) an aliphatic amine compound of formula (ia), (R1-NH2), R1-NH-R2, NH2-(CH2)n-NH2 and comprising morpholine, 3-(aminomethyl)-3,5,5-trimethyl-cyclohexanamine and 4-((4-aminocyclohexyl)methyl)cyclohexanamine or (B) an aromatic amine compound of formula (ib) and (ib1) to (ib8) and comprising 1,2,3,4-tetrahydro-quinoline, 1,2,3,4-tetrahydro-isoquinoline and 4-((4-aminophenyl)methyl)aniline. The alcohol is (C) an aliphatic alcohol compound of formula (ic), (R1-OH-R2), (OH-(CH2)n2-OH), (OH-CH2-CH2-O-CH2-CH2-OH) and (OH-CH2-CH2-CH2-O-CH2-CH2-CH2-OH) or (D) an aromatic alcohol compound of formula (id1) to (id7).    R1, R2 = a linear or branched 1-18C-alkyl or H;    R1a, R2a = a linear or branched 1-18C-alkyl, H, methoxyl, phenyl, phenoxyl, fluorine, chlorine, bromine, or iodine;    m = 1-6;    n = 1-12;    n1 = 0-12;    n2 = 2-8; and    n3 = 1-4.