Distributions of natural gamma-emitting radionuclides were determined in 93 oil samples collected from some petroleum fields in the weste desert of Egypt. The radioisotope activities in the area under investigation lay in tivities could be on account of differences in TDS, HCO3, and Ba, with high or low pH. In this environment, oil properties differently affected the mobilization of natural radionuclides. The range of 226Ra variation had been compared cation (B) and (E) respectively, which was less than the accepted value.