A method for producing an L-amino acid, which comprises inserting a gene which codes for an enzyme which is utilized on the route of biosynthesis of an L-amino acid product into one of at least two plasmid vectors which have compatible replicating origins different from each other, inserting a second gene which codes for an enzyme different from the first enzyme on the route of biosynthesis of the L-amino acid into a second of the plasmid vectors; introducing the thus obtained recombinant plasmids into a strain of Coryneform bacteria; and culturing the thus transformed strain which is capable of producing the L-amino acid, said two enzymes being highly rate determining enzymes for the biosynthesis of L-amino acid.