Effective glycemic control plays an important role in preventing chronic complications of type 2 diabetes mellitus. Oral antidiabetic drugs (OADs) often are the mainstay of treatment. However, type 2 diabetes is a progressive illness which most patients experience a progressive deterioration in glycemic control, OADs also may not achieve or maintain glycemic control. In this setting, adding basal insulin to ongoing OADs is recommended as the next step therapy in the current consensus algorithm for the initiation and adjustment of therapy of the American Diabetes Association (ADA) and the European Association for the Study of Diabetes (EASD). Basal insulin include NPH insulin, insulin glargine and insulin detemir. Insulin glargine and insulin detemir have similar glycemic control, but less hypoglycemia than insulin NPH, and both are also available in pen devices to make their use more simper for patients. Therefore, insulin glargine and insulin detemir are getting more and more popular in the clinical use because they can help overcome some traditional barriers to insulin therapy. The article will review the current knowledge about long-acting insulin analogs in type 2 diabetes to help clinical health care providers in using basal insulin.