The judiciary said in a statement Tuesday the verdicts include death sentences for five people convicted of carrying out terrorist activities, Iran's government-backed Press TV reported.
"Around 81 people have received prison sentences ranging from 6 months to 15 years with three of them getting suspended jail terms," the statement said.
Three defendants were cleared, the statement said.
Meanwhile, the first day of the trial of French academic Clotilde Reiss, also arrested during the protests, adjourned Tuesday with the defense presenting its opening statement, CNN reported Wednesday.
A second court session for Reiss, 24, has not been scheduled, the Fars News Agency said.
Reiss was among the roughly 4,000 people arrested for demonstrating against the June 12 presidential election. Thousands of Iranians rallied against the official result, which declared hard-line President Mahmoud Ahmadinejad the winner in a landslide over his nearest challenger.