Objective: a descriptive and practical study was conducted on a random sample of 150 infants had taken from child health care centers in Basrah governorate (Iraq), who fed on breast milk or dried formula milk and involved males with females at age 1month old and they were followed for the full 12 months of their lives to show the impact of the milk type on the child’s health , growth and body characteristics. Results: The most remarkable results showed that all infants were had their own vaccines. 40.9% of breastfed babies were dynamically active , while 100% of formula lactation babies were inactive and lethargic . All breastfed babies were not refuse suckles from mother breast while formula fed babies were refuse. Also , 27.3% of breastfeeding babies had diarrhea and vomiting compared to 72.7% who didn’t had , whereas an opposite ratios 75% , 25% was in formula feeding babies . Moreover , 27.3% of breastfed babies were had a walking delay compared to 67.9% of formula fed babies. In body measurements, the breastfeeding babies were gain weight more over formula lactation babies, where the average weight gain was 12-18gm in 4-20 weeks and increased to 46gm in 48 weeks post-birth. In favor of breastfed infants, the head perimeter growth rate was 2-3 cm between the months of 5-12 and the rate of increasing body length was 4-5 cm per month , along full year of their age. Conclusions: Mother's milk ensures a healthy and optimal infant diet that meets all of the infant's nutritional needs that help the child grow more efficiently in terms of motor and skill activity, as well as psychological and cognitive development, which is socially reflected by improved parent-child relationship. It has a strong effect on naturally increasing of weight, height and head size, increases immunity and prevents diseases such as scurvy and rickets.