Human milk provides all necessary nutrients for growth of the term infant. Furthermore, in addition to universally recognized nutrients, human milk contains a number of non nutritive components that are likely top play a role in supporting infant growth. In addition, it also contains bioactive compounds responsible for a wide range of beneficial effects, such as the promotion of immune system maturation and protection against infections. The isolation and identification of oligosaccharides and bacteria with beneficial effects for the host provides scientific support for the supplementation of infant formula with these oligosaccharides and bacteria, in order to advance toward the main target of these formulas, to mimic the functional effects observed in breastfed infants. Oligosaccharides with prebiotics functions and selected straims of bacteria with probiotic functions have recentely bee added to infant formulas in the European Union and other countries. However, the Committee on Nutrition of the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition systematically reviewed published evidence on the safety and health effects of the administration of formula supplemented with probiotics and/or prebiotics. The Committee concluded that for healthy infant, at present, there is insufficient data to recommend the routine use of probiotic- and/or prebiotic-supplemented infant formulas. The aim of this review is to analyze the scientific basis for the addition of these compounds to milk formulas.