The three-judge panel sentenced 11 people to death and 71 to life imprisonment, J.M. Ntete, prosecutor for Butare province, said Monday.
The crimes were committed during the 100-day slaughter in mid-1994 in which at least a half-million people were killed, most of them members of Rwanda's Tutsi minority. Political moderates from the Hutu majority were also victims.
Those who received the death penalty — including a deputy mayor were convicted of being planners and masterminds of the slaughter.
The mass trial, which ended Aug. 1, involved 139 defendants. It was held in a temporary courtroom in Mugusa, one of the thousands of settlements that dot Rwanda's rolling green hills — and the site of the crimes.
"It was rare that just one person in a settlement or neighborhood took part in the killings, so we are grouping all the defendants from a certain place so they can be tried together," Justice Minister Jean de Dieu Mucyo said.
The tribunal also sentenced 18 people to prison terms ranging from one year to 25 years, and acquitted 39 people.
The trial was one of many taking place throughout this tiny central African nation of 8 million people. On average, between 30 and 40 defendants appear before each tribunal, the justice minister said. Whenever possible, the trials are held where the crimes took place.
Rwanda's genocide was orchestrated by a government of extremist Hutus who passed orders and distributed hundreds of thousands of machetes to killing gangs throughout the country known as Interahamwe, or "those who pull together."
In neighboring Tanzania, a U.N. tribunal also is trying people indicted on major genocide charges in Rwanda's war. The maximum sentence that tribunal can hand down is life in prison.
Since Rwanda began trying those accused in the genocide, more than 400 people have received the death sentence but only 26 have been executed.
Some 120,000 prisoners in Rwanda are awaiting trial on genocide charges in overcrowded jails. Trying to clear the backlog, authorities released some prisoners facing lesser charges to their home areas, where they face trial in local courts.