Statins have been associated with an increased risk of new-onset diabetes mellitus (NODM), as confirmed in previous observational studies and meta-analyses. Controversy exists as to whether this risk varies depending on statin type or dose. However, there appears to be unanimity regarding the different associated factors that raise this risk. Furthermore, diverse pathophysiologic mechanisms have been described that could explain the increased risk of diabetes in patients with statin treatment. These fundamentally cause a rise in insulin resistance together with a decrease in insulin secretion. The present review aimed to describe the relationship between statin treatment and the presence of diabetes and provide an update of previous published evidence and the possible mechanisms involved.