Background: Gastroenteritis is a disease of gastrointestinal tract. The development of drug resistance in patients suffering from gastroenteritis is due to irrational prescribing behaviour. Thus this study was carried out to assess the pattern of antibiotic use in the treatment of patients with acute gastroenteritis Methodology: This present study was an observational, cross-sectional study carried out in general medicine inpatient unit of tertiary care hospital. Study duration was 4 months. Result: Prescription of patients suffering from acute gastroenteritis were collected. Data was collected by conducting face to face interview of patient and from patient medical record. The data was analyzed by using descriptive statistical analysis method. A total of 100 prescription of patient with acute gastroenteritis admitted in tertiary care hospital during January 2017 to April 2017 were collected. Out of 100 patients 64% were female and 36% were male. Mean age of female and male was 43.54 and 48.38 years respectively. Chief complaints of patients were diarrhea (100%), vomiting (87%), fever (72%) and abdominal cramps (70%) Patients prescribed with antibiotic were 76% and those who were not prescribed with antibiotics were 24%. Ornidazole and ofloxacin combination drug were highly prescribed. Stool test was conducted for 16% of the patients. There was no detection of ova or parasite Conclusion: Antibiotics were not prescribed to 24% of patients suffering from acute gastroenteritis. Antibiotics were prescribed to majority of patients (76%) and it was empirical therapy. Antibiotic should be used rationally. Irrational use of antibiotic can cause antibiotic resistance. Awareness about antibiotic resistance development needs to be provided to prescribers continuously. Key words: Antibiotic rational use, gastroenteritis, Antibiotic resistance, diarrhea, Empirical therapy