Ahmed Mansoor has since 2006 campaigned for freedom of expression and greater political and civil rights in the United Arab Emirates, and
successfully pushed for the liberation of two bloggers jailed for highlighting social problems in the country.
On Tuesday, he was awarded the Martin Ennals award, named after the former secretary general of Amnesty International.
The prize is given to human rights defenders who show deep commitment to their cause despite huge personal risk.
"Ahmed Mansoor is one of the few voices within the United Arab Emirates who provides a credible independent assessment of human rights developments in the country," the Martin Ennals Foundation said on its website.
Mansoor was sentenced to three years in prison in 2011 in a trial criticized by rights groups as "grossly unfair".
At the time, he stood accused, along with four others, of using the Internet to insult the UAE's leaders, of calling for a boycott of elections and of being linked to anti-government demonstrations.
He was pardoned by the UAE's president later the same year, but was stripped of his passport and barred from overseas travel.
The Martin Ennals award was created in 1993, two years after Ennals died.
Its jury is composed of Amnesty International, Human Rights Watch, the International Commission of Jurists and seven other international campaign organizations.
The winner receives a prize of 20,000 Swiss francs ($20,700).
The debut recipient in 1994 was Chinese rights activist and former political prisoner Harry Wu, who moved to the United States in the mid-1980s.
The award can also go to a group.