Byalyatski's wife Natallya Pinchuk received the award on behalf of the political prisoner.
A prize-giving ceremony was held in Berlin on November 22, Radio Racja reports.
Ales Byalyatski was awarded for his efforts in protecting human rights in authoritarian Belarus.
"I am here because Ales is unable to come while he is in prison. The prize is a high appreciation of his work,"Natallya Pinchuk said.
Ales Byalyatski earlier refused to accept the monetary part of the prize – € 10,000 – and asked to spend the money on human rights activity in Belarus.
Besides Natallya Pinchuk, Ales Byalyatski's aide Valyantin Stefanovich and head of the Belarusian Helsinki Committee Aleh Hulak arrived in Berlin. They had meetings with German government commissioner for human rights, a German-Belarusian parliamentary group and representatives of the Ministry of Foreign Affairs.
The Petra Kelly Prize was founded in 1998 to award people or groups of people for their outstanding achievements in respecting human rights, fostering non-violent conflict resolution and protecting the environment. The was award founded in memory of Petra Kelly (1947-1992), a prominent political activist who took part in formation of the German Green Party. Prize winners in the recent years were Russian lawyer and human rights defender Yuri Schmidt, Chinese lawyer Zhang Sizhi, Kenyan human rights and environmental activist Wangari Maathai, who later won the Nobel Peace Prize.