OBJECTIVES: The importance of fathers in ensuring child health in rural developing populations is questioned by anthropologists and population health scientists. Existing literature focuses on paternal death and child mortality. A relative lack of studies consider alternative forms of father absence and/or more subtle health outcomes. Here we determine the frequency and form of father absence in northern Tanzania, and its relationship to household food security, wealth, and child anthropometric status. METHODS: We conducted a cross-sectional survey of 3136 children under 5 years of age from 56 villages. Using multilevel regression we contrast children residing with both parents to those that (i) have experienced paternal death, (ii) reside with their mother but not their living father and (iii) are fostered apart from both living parents. RESULTS: Of the total, 3.5% of children had experienced paternal death. Thirteen percent resided with their mother but away from their living father. Supporting data indicate such cases primarily reflect parental divorce/separation, extra-marital birth, or polygynous fathers residing with an alternative cowife. Paternal death and residing apart from one's living father was associated with lower food security and/or relative poverty and there is suggestive evidence that children in such circumstances achieve lower height-for-age. Six percent of children were fostered, usually with grandparents, and were comparable to children residing with both parents in terms of household food security, wealth, and anthropometric status. CONCLUSION: Our results highlight diversity in the form and consequences of father absence. We discuss limitations of the current study and wider literature on fatherhood and make suggestions for future research.