The prevalence of leukoedema, preleukoplakia and leukoplakia has been studied among 1226 Papuans and New Guineans in two coastal areas and in one highland area. Leukoedema is found in 2.4‐16.9%, preleukoplakia in 10.6‐ 13.4% and leukoplakia in 3.1‐6.2%. Chewing and smoking habits seem to be associated with varying rates of the conditions recorded. In view of a previously supposed obvious association with the betel chewing habit, it is deeply interesting that the results of this study indicate that smoking may be more closely associated with the risk for these conditions. Epithelial atypia, carcinoma in situ or carcinoma were not noted among 26 biopsies taken from the lesions studied.