Abstract:The specific activity of natural gamma emitters like actinium ( 228 Ac), bismuth ( 212 Bi, 214 Bi), lead ( 212 Pb, 214 Pb), potassium ( 40 K), radium ( 224 Ra), thallium ( 208 Tl) and artificial radioisotope caesium ( 137 Cs) was measured in 2005 in the surface layer of marine sediments in the northern Svalbard: Wijdefjorden, Woodfjorden, Vestfjorden and Bockfjorden as well as in the freshwater reservoirs in Andre Land. Nonuniform spatial distribution of these radionuclides was found. Sediment sample from Bockfjorden had the highest specific activities of all natural radionuclides. The specific radioactivity of 137 Cs was much lower than specific radioactivities of natural radionuclides but there were differences between investigated locations. The distribution of 137 Cs is similar to persistent organic pollutants of the lake sediments in the area.