The aim of this investigation was to assess the role of predictors of caries experience among children in urban and rural areas of northern Tanzania. Children of the different communities had varying dietary habits and consumed water with varying fluoride (F) concentration. Subjects (n=256) aged 9-14 years were examined in high-F areas (3.6 mg F/l, Arusha and Arusha Meru, n=101) and low-F areas (<0.4 mg F/l, Moshi and Kibosho, n=155). Dental caries was assessed under field conditions using the decayed, missing, filled teeth (DMFT) index and the WHO criteria. The prevalence of caries was 14%. The mean DMFT score was 0.22 (n=256), the range between areas 0.07-0.66. Carious lesions were mainly observed in mandibular first molars. Logistic regression analyses indicated that subjects in the high-F and urban Arusha municipality were at a significantly higher risk of dental caries than children in the low-F areas (odds ratio [OR] 2.6). Controlling for ethnicity, children in urban areas were at higher risk for caries (OR 5.4) than children living in low-F rural Kibosho.