Background: Nowadays Bottle-feeding has become a practice in developed countries and urban communities of developing countries. There is a current shift from traditional feeding practice towards shorter breastfeeding and introduction of bottle-feeding. Feeding bottles are associated with diarrheal disease morbidity and mortality as it is difficult to keep it clean especially in developing countries. There is no study conducted in Ethiopia showing Assessment of under nutrition and the Prevalence of Infections, Allergy and Diarrhea among Bottle Fed Infants and Its Comparison with Non bottle fed infants, hence this study will provide an insight to practitioners, researchers, and policy makers. Objective: To assess the under nutritional Status and the Prevalence of Infections, Allergy and Diarrhea among Bottle Fed Infants and its Comparison with Non bottle fed infants Aged 6-23 Months in Bole Sub City Health Centers, Addis Ababa, Ethiopia: Method: Institutional based case-control study was conducted from Nov 02-Nov 30, 2020 in Bole sub city health center, Addis Ababa Ethiopia. A total of 52 cases and 103 controls were studied. Four health centers were randomly selected from Bole sub city and 162 mothers who brought children to the health center were randomly selected and interviewed. Interviewer administered questionnaire was used to collect the data. Data were collected by trained data collectors using structured questionnaires at facility setting. Data was entered and analyzed using SPSS v20. Effects of bottle feeding were identified using multivariate analysis. Results: Among the total of 52 cases 53.8% were wasted as compared to controls, thus there were higher significant association between wasting and bottle feeding (AOR= 3.384, 95% C.I.: (1.330-8.60). Among other factors that were associated with bottle feeding, Mothers who delivered their child with Cesarean Section (AOR= 4.091, 95% C.I: 1.59, 10.52), Husbands who works in a governmental organizations (AOR= 5.032, 95% C.I: 1.866, 13.567) and diarrhea were associated with bottle feeding (AOR =3.471, 95% C.I.: 1.07, 11.16). Conclusion and Recommendation: This study has found that wasting, diarrheal infection; Mode of Delivery and Husband Occupation had significant association with Bottle feeding. Therefore, counseling should be VI given to mothers about the effect of bottle feeding and use of appropriate feeding to tackle under nutrition in children. Key Words: Bottle Feeding, Stunting, Wasting, and Underweight