Background: Low birth weight is one of the public health problems in the globe and it is an indicator of the health of the newborn survival and the mother’s nutrition and health status. This study was aimed to determine the prevalence of low birth weight and its associated factors among mothers who gave birth at Bahir Dar Felege Hiwot referral hospital. Methods: A cross-sectional facility based study was conducted from March 18 to May 18 / 2015. A total of 662 mothers were included in the study.The data was entered and analyzed using SPSS version 20 software. Bivariate and multivariable logistic regression was used to identify factors associated with low birth weight. Results: The prevalence of low birth weight was found to be 11.6%. Age of the mothers (20-34 years) AOR= 0.4(95% CI: 0.19-0.93), low income AOR=2.6 (95%CI: 1.16-6.05), gestational age < 37 weeks AOR=18.2 (95% CI:9.26-35.94), MUAC<23 cm AOR =3.4 (95%CI:1.38-8.60) and pregnancy induced hypertension AOR=6.5 (95%CI:3.06-14.0) were factors associated with low birth weight. Conclusion: The prevalence of low birth weight was in line with WHO estimate for sub-Saharan Africa. Nutritional counseling and early detection and management of pregnancy induced hypertension is recommended.