Child health outcomes are related to the mother's nutrition during pregnancy and the baby's diet throughout infancy. The child's intestinal microbiome is the main source of postnatal immunological activation, which is linked to both health and disease in children. Nursing exclusively is advised for the first six months of a baby's life; otherwise, dairy-based infant formula is a supplement to breastfeeding. Numerous studies have shown that breastfed newborns have a different makeup of gut flora compared to infants fed formula. To highlight the important differences between human milk and infant formula in the development of the early intestinal microbiota and immune system, this study attempts to ignore any plausible explanations for some of the risks and benefits associated with human milk and infant formula. The approach was a literature review. A comprehensive search was done on the Pubmed Central® search engine. Using the Boolean operators "AND" and "OR," the search terms used are "breastfeeding," "formula," "microbiota," "intestinal," "human milk," and "infant." Among all the publications purchased, articles comprising various types of studies relevant to the literature review topic were picked. Breastfeeding is the preferred baby-feeding strategy. If exclusive breastfeeding is not preferred, infant formula prepared from cow's milk should be altered to promote the development of the infant's gut flora. Formulations could be modified by adding probiotic or prebiotic oligosaccharide agents.