A process for producing an L-amino acid such as L-lysine or L-glutamic acid by an improved fermentation method compared with the conventional methods which comprises transferring a gene encoding succinate dehydrogenase into a coryneform bacterium capable of producing an L-amino acid such as L-lysine or L-glutamic acid and thus enhancing the succinate dehydrogenase activity to thereby elevate the L-amino acid productivity; and strains to be used in this method.