OBJECTIVES: Compares real world treatment patterns for T2DM in Japan and the United States (US). METHODS: Retrospective analysis was conducted using administrative claims data from MarketScan® Commercial and Medicare and JMDC Claims Database databases (1/1/2009-12/31/2014). Adult T2DM patients (MarketScan n=233,058; JMDC n= 18,006) were included if they were newly treated with oral hypoglycemic agents. The index date was the date of first treatment.  First and second line treatment patterns are compared during a 6-month follow-up. RESULTS: Patients were predominately male (52% US; 72% Japan) with mean age of 58 years in the US and 51 years in Japan. The majority of patients initiated treatment with a monotherapy (US 87%; Japan 85%).  In the US, biguanides (74%), sulfonylureas (14%) and dipeptidyl-peptidase inhibitors (DPP4-i) (6%) were the most common monotherapies compared to Japan where DPP4-i (45%) was the most common followed by biguanides (22%), sulfonylureas (12%) and alpha-glucosidase inhibitors (12%). The majority of patients remained on their index therapy for the entire follow-up (54% US; 60% Japan);16% of the US and 23% of Japanese patients switched to a different treatment. Second line therapy predominantly used ≥2 drug combinations (US 71%; Japan 73%) with the most common being biguanides/sulfonylureas (40%) and biguanides/DPP4i (19%) in the US and biguanides/DPP4-i (26%) and DPP4-I/sulfonylureas (16%) in Japan. CONCLUSIONS: In Japan and the US, T2DM oral hypoglycemic treatment was initiated most often as monotherapy; however, the types of drugs used differed between the countries. Despite initiating monotherapy with dissimilar medications, the majority of patients in both countries remained on their initial therapy during the entire 6 months of follow-up. Patients switching medications during the follow-up period predominantly used combination therapy. Whether in combination or monotherapy, the most commonly used class of oral hypoglycemic agents in the US was biguanides and was DPP4-i in Japan.