Background: The inappropriate and irrational use of antibiotics both in humans and animals causes bacterial resistance. Bacterial resistance is common in low- and middle-income countries, including Bangladesh. Bangladesh has very limited information on antibiotic use and associated resistance. We sought to better understand antibiotic use in low-resource settings for the development of effective strategies to address inappropriate antibiotic use. Methods: We conducted a cross-sectional study among hospitalized children <5 years of age in a tertiary-care hospital in Barishal, Bangladesh, to collect data on antibiotic use. We collected data from 400 children during February–April 2019. Results: Among these 400 children, >50% were aged <1 year, and >60% of these children were boys. The average hospital stay was 3 days (range, 1–14). Most of the children had history of diarrhea and 18% had pneumonia. Most children (82%) were prescribed antibiotics. A combined form of antibiotics was prescribed for 17% of these children. In total, 14 different antibiotics were used. The most commonly used antibiotic was ceftriaxone (57%) followed by azithromycin (14%). The parental route was mostly preferred (75%) for antibiotic administration. Conclusions: Antibiotic prescription was common in children aged <5 years visiting a tertiary-care hospital. Most of the prescribed antibiotics were broad spectrum, which can promote bacterial resistance. Further studies are needed to identify the factors associated with overuse of antibiotics and bacterial resistance in low-resource settings.