The exhibition, called "Chechnya: The Final Solution," was organized by Polish rights activist Adam Borowski. It includes many graphic scenes of violence.
Library Director Martin Punta told RFE/RL's North Caucasus Service that each of the photos is covered with a black cloth so that visitors can decide if they want to lift the cloth and see the image.
Borowski tried to hold the exhibit at the European Parliament in Brussels last year but officials prevented it from appearing after declaring that some of the pictures were "repulsive."
(RFE/RL correspondents Claire Bigg and Amina Umarova have written a compelling account of the efforts to identify Chechnya's dead and missing.)