Summary The over-all prevalence of intestinal parasites in arctic Greenland was 72%. The corresponding rate in Alaska, also based on a single stool examination, was 42%. In the Scandinavian arctic where social and climatic conditions approximate those of north temperate regions, the prevalence was 11%. The Disko Bay population of Greenland differed from its Eskimo neighbors of arctic Canada and Alaska and from residents of Finnish Lapland in an absence of Diphyllobothrium species. The observed prevalence of Entamoeba histolytica in arctic Greenland was 16%, but clinical amebiasis apparently was responsible for only a small part of the prevailing acute intestinal disease.