Hashemi-Rafsanjani was elected by fellow members to chair the Assembly of Experts, a body of 86 senior clerics that supervises the work of Supreme Leader Ayatollah Ali Khamenei.
Hashemi-Rafsanjani's main rival for the post had been Ayatollah Ahmad Jannati, the head of the conservative Guardian Council.
The post had been vacant since the death in July of Ayatollah Ali Meshkini.
The pro-reformist Hashemi-Rafsanjani, who was president for most of the 1990s, was beaten in the 2005 presidential election by Mahmud Ahmadinejad.
RFE/RL Iran Report
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