The natural L(+) lactic acid of highest purity is produced by fermentation. It is the transprarent, colorless syrupy liquid with a mild acid taste, the optical purity is above 98.0%, the color is 10 APHA down, and the other inspection items pass or surpass the specifications of USP (25 edition), JSFA(1999 edition) and Brewing (1990edition). The natural product is widely used in the fields of food, pharmaceutical and chemical industry