Tuberculosis is one of the most important communicable diseases worldwide. Its Antituberculosis therapy (ATT) has multiple side effects, out of which ATT induced hepatitis is important one, as it can force the Physicians to modify the treatment. Objective: To determine the frequency of first line Anti Tuberculosis drugs induced hepatotoxicity during intensive phase of treatment. Subject and Methods: This was a descriptive case series study conducted at multicenter during July 2018 to December 2018. In this study, 150 patients of either gender with age range of 15 to 60 years were selected by non-probability consecutive sampling after fulfilling the inclusion and exclusion criteria. They were started on category 1 of ATT. They were then followed for two months for the development of ATT induced hepatitis, which was monitored with the help of clinical symptoms and liver enzymes. Results: In present study, there were total 150 cases out of which 80 were male and 70 females with mean age of 34.28± 15.28 years. There were 115 cases suffering from PTB and 35 from EPTB. ATT induced hepatotoxicity was found in 17 out of 150 patients (11.33%). Among these 17 hepatotoxic patients 10 were males and 7 were females (p=0.63). ATT induced hepatitis was more seen in cases of PTB where it occurred in 15 cases (p= 0.14) and among the PTB, the highest was seen in far advanced TB (47.8%), which was statistically significant (p = 0.026). Highest incidence of hepatotoxicity (22.5%) was found in age group of 49 to 60 years, which was statistically significant (p= 0.036). Majority (13 out of 17) developed it within first 30 days. Conclusion: ATT induced hepatitis is a common side effect. About one in every nine case develops it. Old age and Pulmonary disease, especially far advance disease is associated with higher risk of hepatotoxicity. Key Words: Tuberculosis, Hepatitis, First line ATT.