Reformist figures and journalists facing prosecution in fourth trial.
Behzad Nabavi, Kian Tajbakhsh, Mohammad Qochani, Saeed Laylaz, Masoud Bastani, Mohsen Safaeai Farahani, Mohsen Mirdamadi are among the defendants. Iran has already set mass trials of around 140 people on offences linked to the massive post election protests.
At previous hearings the defendants have included top reformists, political activists, a young French woman lecturer and two employees of the French and British embassies.
Ahmadinejad’s election victory triggered massive street protests in Tehran and other cities.
Officials have said at least 30 people were killed in clashes with security forces, but the opposition puts the death toll at 69.
About 4,000 people were initially detained over the protests and hundreds are still behind bars.