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The contents of natural radionuclides (Ra-226, Th-232 and K-40) were measured in sedimentary phosphate rock samples (Abu-Tartur phosphate, Western Desert Egypt) by using gamma spectrometry (NaI (Tl) 3 ’’ x 3 ’’). Phosphate and environmental samples were collected from Abu-Tartur phosphate mine and the surrounding region. The results are discussed and compared with the levels in phosphate rocks from different countries. The activities of Ra-226, Th-232 series and K-40 are between (14.9 +/- 0.8 and 302.4 +/- 15.2), (2.6 +/- 1.0 and 154.9 +/- 7.8) and (10.0 +/- 0.5 and 368.4 +/- 18.4) Bq kg(-1), respectively. The Abu-Tartur phosphate deposit was found to have lower activity than many others exploited phosphate sedimentary deposits, with its average total annual dose being only 114.6 mu Sv y(-1). This value is about 11.46% of the 1.0 mSv y(-1) recommended by the International Commission on Radiological Protection (ICRP-60, 1990) as the maximum annual dose to members of the public.