The first total synthesis of biselyngbyaside, an 18-membered macrolide glycoside, was achieved. The glycoside bond was introduced using the Schmidt method before construction of the 18-membered ring due to the instability of the conjugated diene and the β-hydroxy ester moiety. The macrolactone ring was constructed using the Mitsunobu reaction followed by intramolecular the Stille coupling reaction.