dl-Muscone was prepared through acyloin cyclization of dimethyl β-methyl-pentadecanedioate,which was synthesized from anodio coupling of half methyl ester of dodecanedioic acid and that of,β-methylglutaric aoid.Separtion of dl-muscone from its isomerio γ-methyl compound was achieved by silica-gel column chromatography,The result shows that ratio between dl-muscone and its γ-methyl isomer is about 7:3.