Objective: To determine the association between low birth weight and household food insecurity at govment hospitals in Addis Ababa, Ethiopia.Methods: A case control study was carried out on 468 mothers with term neonates from February 1, 2017 to May 15, 2017. The cases were women who gave term babies weighing less than 2500 g and the controls were those having 2500 g or above. In the included hospitals, choices of cases were done as the cases found and the next three eligible newbs in the matity room were the controls. Data were collected by using pretested and structured questionnaire. Standard beam balance was used to measure the neonatal weight by trained midwifery. The data were entered into a computer using Epi-Data 3.1 and exported to Stata version 14 for data management and analysis. Results: Mothers having food insecurity [adjusted odd ratio (AOR) 3.58; 95％ confidence interval (CI) (1.79-7.16)], mid-upper arm circumference [AOR 7.70; 95％ CI (4.39-13.60)], hypertension [AOR 4.81; 95％ CI (2.33-9.93)], and early age [AOR 3.88; 95％ CI (1.35-11.15)] showed statistically significant association with low birth weight. Conclusions: Household food insecurity, hypertension, mid-upper arm circumference and early age in women were significant predictors of low birth weight. The provision of adequate nutrient for pregnant mothers having household food insecurity should be assured in order to prevent adverse birth weight outcomes.