Farai Maguwu, head of the Centre for Research and Development, was arrested last month following a meeting with a Kimberley Process representative who was probing whether Zimbabwe met human rights standards for the diamond trade.
He remains in custody after he was denied bail Friday.
Maguwu’s group regularly provided information about abuses in the eastern Marange mines to the Kimberley Process, which documented gross military abuses against civilians.
“Maguwu is being persecuted for carrying out his lawful work of monitoring and documenting alleged human rights violations by security forces at some of Zimbabwe’s richest diamond fields,” said Amnesty’s Africa director, Erwin van der Borght.
“We consider Maguwu a prisoner of conscience and call on the authorities to release him immediately and unconditionally.”
Right groups say Zimbabwe has failed to keep a promise to halt abuse of diamond miners and should have its international certification frozen.
Kimberley monitor Abbey Chikane said President Robert Mugabe’s government had met the global diamond regulator’s criteria.
But Kimberley failed last month to agree on whether to allow Zimbabwe to resume trade. The matter will be discussed again next week in Saint Petersburg. AFP