Objective To explore the clinical characteristics of hypoglycemia patients who were admitted to the emergency department with symptoms resembling hypoglycemia. Methods In our study, 290 hypoglycemia cases were evaluated from January 2010 to December 2010. Results The mean age is 66.1 yrs old. The mean glucose level is 41.8mg/dL. Of 290 hypoglycemia cases, 239 (82.4%) cases are receiving treatment for diabetes mellitus (62 using insulin, 190 receiving oral anti-diabetics, and 13 using both OAD and insulin). The most common cause of hypoglycemia is loss of appetite. Among other reasons, there are malignancies (78, 26%), infection (25, 8%), chronic liver disease (15, 5%), OAD(oral anti-diabetics) use by mistake (10, 3.6%). Conclusion Diabetes mellitus is the most common reasons for hypoglycemia in patients seen in emergency departments. Risk factors of patients admitted to emergency department with hypoglycemia are loss of appetite, malignancies, infection, chronic liver disease, OAD use by mistake. Efforts should be made as to prevent hypoglycemia through training patients on better grounds.