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Different types of granites, used extensively in local construction, were collected from five localities in Egypt, namely: Abu Ziran (Central Eastern Desert), Gabal El Maesala (Aswan) and three areas from Wadi Allaqi, (Gabal Abu Marw, Gabal Haumor and Gabal um Shalman), in the South Eastern Desert. Granite samples were studied radiologically, petrographically and geochemically. The contents of natural radionuclides (Ra-226, Th-232 and K-40) were measured in investigated samples by using gamma spectrometry [NaI (Tl) 3’3’]. The activity concentrations of Ra-226, Th-232 and K-40 in the selected granite samples ranged from 90.5 to 1117, 81 to 754 and 1006 to 79040 Bq kg(1), respectively. The external hazard index (H-ex), absorbed dose and annual effective dose rate were evaluated to assess the radiation hazard for people living in dwellings made of the materials studied. The calculated radium equivalents were lower than the values recommended for construction materials (370 Bq kg(1)). The excess lifetime cancer risks were also calculated. Petrographically, the granites studied are varied in the form of potash-feldspar, quartz, plagioclase, mica and hornblende. The accessory minerals are zircon, apatite and allanite. Geochemically, the chemical composition of the granite is studied especially for major oxides. They are characterized to have SiO2, K2O, Na2O and Al2O3 with depletion in CaO, MgO, TiO2 and P2O5.