Turkish cartoonist Musa Kart, centre, protests outside an Istanbul courthouse in March
The Swiss group hands out the honour, known as its International Editorial Cartoons Prize, every two years.
“The jury has chosen Musa Kart, iconic cartoonist of the Istanbul newspaper Cumhuriyet, for his talent and courage in the defence of freedom of expression,” a statement from the group said.
Cumhuriyet — which means simply “Republic” — was set up in 1924 after the Turkish republic was founded in 1923.
It has been fiercely critical of President Recep Tayyip Erdogan and has run front-page stories that have angered the Turkish head of state.
A Turkish court last month handed out multiple sentences to 13 journalists and executives from the paper for “aiding and abetting terror organisations”, but the group remains free pending appeal.
Kart was sentenced to three years and nine months in prison.
The prize was judged by an official from Geneva’s government, the head of Human Rights Watch Kenneth Roth, along with cartoonists from leading publications including Le Monde, the New York Times and The New Yorker.
“Musa Kart is both a witness and especially a victim of the deterioration of freedom of expression in Turkey,” a Le Monde cartoonist known as Plantu said a statement.
Kart has denied the allegations against him.
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