Ketosis-prone type 2 diabetes (KPD) has been characterized as diabetes with severe insulin deficiency at diagnosis associated with ketosis or ketoacidosis without a precipitating cause. Improvement in beta-cell function and insulin sensitivity by aggressive diabetic management could allow discontinuation of insulin therapy within a few month of therapy. These subjects are usually obese, have a strong family history of diabetes, absence of β-cell autoimmune markers and lack of human leukocyte antigen genetic association. This clinical presentation has been reported primarily in African and African Americans, but rare in Asian and white person. We recently experienced a case of KPD in Korea and present it with literature review.