Ganji, who served a six-year jail sentence for articles denouncing the murder of Iranian opposition intellectuals, was presented the award by Louise Arbour, the UN high commissioner for human rights.
After a hunger strike last year, Ganji was released conditionally in March 2006. He then started a world tour to introduce Iran's democratic movement to western audiences.
While receiving the award in Geneva, he said he was determined to return to his home country.
"The fight [for democracy] takes place inside a country," he said. "I don't want to change the government of Switzerland, I'm fighting to change the Iranian government and for the transition toward democracy in Iran."
The Martin Ennals Award is the top award of the human rights movement. Its jury includes representatives of the world's leading nongovernmental human rights organizations.
Another recipient this year was Arnold Tsunga, a lawyer and radio commentator from Zimbabwe.
(Radio Farda, martiennalsaward.org)