The purpose of this survey was to determine the distribution of terrestrial radionuclides (U-238, Th-232 and K-40) in surface soil samples collected from different locations in and around Osmaniye and assess the radiological implications of outdoor external exposure. The activity concentrations of U-238, Th-232 and K-40 in soil samples ranged from 2.6 to 38.1 Bq kg(1) with a mean of 10.40.7 Bq kg(1), 3.740.5 Bq kg(1) with a mean of 12.20.7 Bq kg(1) and 30.0639.7 Bq kg(1) with a mean of 243.412.8 Bq kg(1), respectively. The concentrations of these radionuclides, presented in this article, were compared with those obtained from similar studies related to Turkey reported in the literature as well as earths crust average values. The results of the activity concentrations were used to assess the external absorbed gamma dose rate (GDR) in outdoor air and the annual effective dose (AED). The outdoor absorbed GDRs fluctuate from 5.2 to 53.6 nGy h(1) with a mean of 22.49.5. The corresponding mean AED is found to be 0.03 mSv.