This article discusses the emergence, ideology, and activities of the Saudi Shi’a opposition group Hizbullah al-Hijaz and its clerical wing, the Tajamu’ ‘Ulama’ al-Hijaz. The group has played a significant but little known role in Saudi-Iranian relations since 1987 following its creation as a rival to the other Saudi Shi’a opposition group, the Islamic Revolution Organization. Hizbullah al-Hijaz was pro-Iranian and followed the Marja’iyya of Ayatollahs Khomeini and Khamene’i. Although it officially denounced any engagement with the Saudi leadership, it profited from a general amnesty in 1993. After it was blamed for the Khobar Towers bombing in 1996, most of its members were arrested and its organization dismantled.