About 50% of young children in Tanzania suffer from protein-energy undernutrition (PEU) while more than 45% of children under the age of five suffer from various micronutrient deficiency disorders. The immediate cause of these conditions is inadequate intake and poor utilization of nutrients, which begins in the weaning period and amplifies in the subsequent years. This study was conducted to assess the potential of some home made and commercial weaning foods commonly consumed in Tanzania to supply adequate amounts of both macro- and micronutrients as recommended in the Tanzania and FAO/WHO Codex Alimentarius Standards for cereal/milk-based weaning foods. Six types of home made weaning foods, maize, cassava, millet, sorghum and millet-sardine-peanut composite gruels and plantain pap, and four types of commercial weaning foods, Cerelac- 1, Cerelac-2, Lactogen-1 and Lactogen-2, popularly consumed in Tanzania, were chemically assayed for proximate composition, energy and mineral density. Results of the study indicated that, both the home made and commercial weaning foods were good sources of macro- and micronutrients. When compared with the Codex Alimentarius and Tanzania Bureau of Standards specifications for weaning foods, both home made and commercial weaning foods had some shortcomings in terms of nutrient composition and energy balance. Many of the foods were low in fat. Fe, Ca, Zn and P but high in crude fiber, carbohydrate and magnesium. Ca, Fe and Zn were the most common deficient macro/micronutrients in the home made weaning foods. In spite of these shortcomings, most of the home made and commercial weaning foods were nutritionally sound since they could provide reasonable percentages of the recommended daily allowances for macro/micronutrients and energy. It is suggested that, more efforts must be directed towards increasing the concentration of Ca, Fe and Zn in the home made weaning foods through supplementation of the starchy staples with mineral rich foods. Meanwhile, the parents, caretakers and health workers should be educated on the selection and preparation of nutritious, balanced weaning foods and good weaning practices.