[en] The objective of this work was to assess the radiation hazards associated gamma rays from building materials. The radon exhalation and uranium contents are also presented. Natural gamma rays activities of natural radionuclide represented mainly by three natural radioactive series ²³⁸U, ²³⁵U, and '2³²Th, and the primordial ⁴⁰K in the samples of building materials consisting of soil, bricks, sand, ceramics, marble and gypsum from different areas of eastern Algeria have been measured using gamma ray spectrometry. The values of the activities of these radionuclides do not clearly reflect the radiation hazard associated with these materials. The radium equivalent (Ra_eq) concentration is, therefore, defined which takes into account the effectiveness of these isotopes in creating the radiation hazard. Radium equivalent activities, external and internal hazard indices (H_ex and H_in) have been calculated from of the activities of ²²⁶Ra, ²³²Th and '4⁰K for suitability of the materials.