This article attempts to address the issue of prisoners of war through the prism of international law. The object of research is the work of the Commission to investigate the Entente's complaints of violation of Hague Convention on Treatment of Prisoners of War by German authorities. After the armistice, the governments of the Entente sent notes to the German authorities on allegations contrary to international law actions in German POW camps. The study analyses the problems of war prisoners' life at the time, particularly their lifestyle, pastime, ceremonies, work, food. Also paper investigates the laws, introduced during ground warfare by the Hague Convention, as well as considers the position of war prisoners in Germany. The new German government (Council of the People's Deputies) set up a commission to investigate the claims of the Entente. During the First World War, all countries kept the international law relating to the treatment of prisoners of the war. Separate violations of articles of the Hague Convention of 1907 based on the objective reasons, they were not connected with the general thrust of internal policy of belligerent states.