The intestinal parasites of the schoolchildren from one rural area and one urban area, both on Pemba Island, Zanzibar, Tanzania, were surveyed within the framework of the local Helminth Control Programme. Stool samples were examined for helminth eggs and protozoa by quantitative (Kato-Katz) and concentration (formalin-ether) techniques. The results indicate that intestinal helminthiases represent a significant public health problem in the study areas. All the subjects were found to be infected with helminths, most (> 97%) with more than one species. Hookworms and Trichuris appear to constitute the most serious challenges to the schoolchildren, both in terms of prevalence and intensity of infection. There were no significant differences between the results from the urban area and those from the rural area. The observations are important in the planning of control activities.