Abstract: Exclusive breast feeding is important practice that should be encouraged for normal growth and development of infants and provide great protection against many diseases. This study is a cross-sectional and non-randomized study that included a total of 343 mother-infant pairs, of which 251 infants were mixed fed, 92 infants were exclusively breast feed for 6 months. The results of growth (weight and length) show similar growth rate between exclusively breast fed infants for six months and infants who had mixed feeding. Head circumference for exclusive breast fed infants was higher than for mixed fed infants. The results also show significantly higher lipid profile (total cholesterol, LDL and HDL) and total protein levels for infants who were exclusively breast fed for six months compared with infants who were mixed fed while no significant differences in serum albumin between two groups was found. The results indicate that infants who were exclusively breast fed for six months had lower number of gastrointestinal tract, respiratory tract and urinary tract infections and otitis media than infants on mixed feeding. Regarding infants development, the current study showed that infants who were breast fed exclusively for six months have earlier gross and fine motor development; also they had early language development than infants who were on mixed feeding. It is concluded that human milk is uniquely superior to infant feeding and it is the healthiest feeding practice for infants and for normal growth and development, because it provides a reasonable protection against many diseases.