Type 2 diabetes mellitus (T2DM) is characterized by progressive β-cell dysfunctioning and insulin resistance. This article reviews recent literature with special focus on inflammatory mechanisms that provoke the pathogenesis of T2DM. We have focused on the recent advances in progression of T2DM including various inflammatory mechanisms that might induce inflammation, insulin resistance, decrease insulin secretion from pancreatic islets and dysfunctioning of β-cells. Here we have also summarized the role of various pro-inflammatory mediators involved in inflammatory mechanisms, which may further alter the normal structure of β-cells by inducing pancreatic islet's apoptosis. In conclusion, it is suggested that the role of inflammation in pathogenesis of T2DM is crucial and cannot be neglected. Moreover, the insight of inflammatory responses in T2DM may provide a new gateway for the better treatment of diabetes mellitus. J. Cell. Biochem. 114: 525–531, 2013. © 2012 Wiley Periodicals, Inc.