Background: Low birth weight (LBW) of neonates is a global problem. It is one of the significant factors for newborn health in the future. Those babies born with LWB, suffer from different diseases, hamper cognitive development and survive undernutrition. Multiple factors influence LBW in pregnancy. This study aimed to find out the common determinants of LBW. Method: A cross-sectional study was conducted at the Department of Gynecology and Obstetrics at Rajshahi Medical College Hospital (RMCH), Rajshahi from May 2019 to October 2019. Pre-tested semi-structured questionnaires were used and collected individual participant information by face-to-face interview. Baby weightier was used to measure babies' body weight. Result: The study findings revealed that 40% of mothers delivered LWB babies while 6.6% had deficient birth weight, 4.4% had very low birth weight, and 22% had low birth weight. The frequency of LWB was high in 30-39 years age group respondents and only 9% in the 40-49 year age group. We also observed a high proportion of LWB neonates among housewife mothers and 5000-15000 TK income family members. Moreover, with three or more than three times meals consumed groups have 20.5% LBW fetuses, Eggs consumed groups 8.0%, and Fruits consumed groups 14.9% respectively. Conclusion: LWB is influenced by the multiple factors of the health system and maternal factors. Insufficient take care of the mother during pregnancy, and lack of food supplements and medicine play vital roles in this consequence. The policymaker should focus on maternal health to mitigate this problem.