We achieved the stereocontrolled syntheses of (-)-loliolide, (-)-xanthoxin, and their stereoisomers from (+)- or (-)-3-alkoxy-6-hydroxymethyl-1,1,5-trimethylcyclohexene through the corresponding syn and anti-epoxides, respectively, which were obtained by utilizing the highly diastereoselective Sharpless asymmetric epoxidation or mCPBA oxidation.