Shahriyar III (Persian: شهریار), was the sixteenth ruler of the Bavand dynasty from 986 to 987, and briefly in 998 after a short disruption during his reign.
Shahriyar III is later mentioned as the ruler of the Bavand dynasty in the following year.
Al-Marzuban is then once again mentioned in sources, as having deposed Shahriyar III, and restored himself as the ruler of the Bavand dynasty.
In 998, Shahriyar III returned to Tabaristan with Ziyarid aid, and captured Shahriyarkuh from al-Marzuban.
Shahriyar III then ascended the Bavandid throne, and declared independence from Ziyarid rule.