Background: Corrosive injuries to the upper gastrointestinal tract are still a major concern in developing countries like India, where the corrosive substances are easily accessible to the common people. The ingestion of corrosive substances produces a spectrum of damage in the upper gastrointestinal tract. Acids affect the stomach more commonly and they cause mucosal damage by coagulation necrosis and require longer duration of contact. On the other hand, alkalis cause liquefaction necrosis and as they are more viscous they tend to adhere to the oesophageal mucosa with only a relatively small amount reaching the stomach. Aim and Objectives of Study: To find out the types of caustic ingestion and the site, degree and extent of injury of the oesophagus and the stomach. Methods: Adult patients presenting with corrosive injury to the department of General Surgery and Surgical Gastroenterology in AIIMS Patna from 2016 to 2018. Total 32 adult patients were included in the study. Acute corrosive poisoning patients without any gastrointestinal symptoms and patients with acute corrosive injury who were haemodynamically unstable or who were suffering from respiratory distress were excluded. Upper G.I.Endoscopy was used to find out the severity and grade of injury of oesophagus and stomach. It was retrospective descriptive study. Grade of injury of oesophagus and stomach was determined by endoscopy based on Zargar’s classification. Result: In our series, all caustic accidents involved acids (100% of cases) and the most frequently ingested agent was muriatic acid also known as hydrochloric acid (90.6%). Contrary to the traditional belief that the oesophagus is spared in acid ingestion, we found oesophageal damage in 25 out of 32 patients with acid ingestion (78.1%). Conclusion: Although alkaline substances account for most cases of caustic ingestion in Western countries, acid ingestion is more common in our society. Muriatic acid is the most common agent used in caustic ingestion in our society.