ABSTRACT Introduction: The bacterial environment of the gastrointestinal tract has long been investigated for its role in health maintenance and relationship to various disease states. In healthy hosts, microorganisms are present throughout the gastrointestinal tract and are essential for gut barrier function, digestive support, and immune homeostasis. Small intestinal bacterial overgrowth (SIBO) is pathology of gut microbiota dysregulation. Aims: To determine the frequency of SIBO in cirrhotics and correlate with severity of cirrhosis. Materials and Methods: This is a prospective observational cohort study. This Study was conducted from January 2021 to October 2021at Department of Gastroenterology, NH Rabindranath Tagore International Institute of Cardiac Sciences. Result: In our study, our patients with cirrhosis had mean age of 43.59 ± 5.04 years and frequency of SIBO in them was 46%. SIBO was more prevalent in patients with decompensated cirrhosis than in patients with compensated cirrhosis. Majority of our patients with cirrhosis belonged to CTP class B followed by class A and C. Frequency of SIBO increased progressively with increase in CTP class. The most common etiology of cirrhosis was alcohol followed by NAFLD, Hepatitis B and Hepatitis C