Abstract: L-carnitine is also named vitamins BT, which chemical name is β-hydroxy-γ-(trimethylammonio)butyrobetaine.There are a lot of methods to synthesis L-carnitine, chiral epichlorohydrin taken as start material is discussed in this paper. L-(-)-3-chloride-2-oxypropyl trimethyl ammonium chloride is produced by reacting chiral epichlorohydrin with trimethylami-
ne hydrochloride. The best yield 94.8% is acquired at the conditions of chiral epichlorohydrin and trimethylamine hydrochloride with the mole rate of 0.95, react at 42℃ for 5 hours. L-(-)-3-cyano-2-oxypropyl trimethyl ammonium chloride is produced by reaction of L-(-)-3-chloride-2-oxypropyl trimethyl ammonium chloride and sodium cyanide, the highest yield 83.7% is obtained at 51℃ for 6 hours by the one-factor experiment. Finally, L-(-)-3-chloride-2-oxypropyl trimethyl ammonium chloride is hydrolysis and then anion exchange to obtain L-carnitine with yield of 78.9%. The overall yield of this process is 62.6%.