Objective This study aims to provide basic data on the types and frequency of chemical ingestions and the clinical outcomes of chemical ingestion injury. Methods This study retrospectively analyzed the data obtained from the Emergency Department-Based Injury In-depth Surveillance of the Korea Centers for Disease Control and Prevention (South Korea) from 2011 to 2016. Patients ingesting chemicals aged ≥ 18 years were included, but those ingesting unknown chemical substances or with unknown clinical outcomes were excluded. Results This study included 2,712 (47.2% were men and 52.8% were women, mean age, 47.05 years) patients ingesting chemicals. Unintentional and intentional ingestions were reported in 1,673 (61.7%) and 1,039 (38.3%), respectively. The most commonly ingested chemical substances were hypochlorites, detergents, ethanol, and acetic acid. In the unintentional ingestion group, the most common chemicals upon admission were hypochlorites (74), glacial acetic acid (60), and detergent (33). The admission rates were 60% for glacial acetic acid, 58.3% ethylene glycol, and 30.4% other alkali agents. In the intentional ingestion group, the most common chemicals upon admission were hypochlorites (242), glacial acetic acid (79), ethylene glycol (42), and detergent (41). The admission rates were 91.9% for glacial acetic acid, 87.5% ethylene glycol, 85.7% potassium cyanide, and 81.4% hydrochloric acid. In total, 79 deaths (10 unintentional ingestions, 69 intentional ingestion) were reported, and glacial acetic acid had an odds ratio of 9.299 for mortality. Conclusion We compared the intentional and unintentional ingestion groups, and analyzed the factors affecting hospital admission and mortality in each group. The types and clinical outcomes of chemical ingestion varied depending on the purpose of chemical ingestion. The findings are considered beneficial in establishing treatment policies for patients ingesting chemicals.