Magnesium is an essential mediator of a vast number of critical enzymatic cellular reactions in the human body. Some clinical epidemiological studies suggest that hypomagnesemia accounts for declines in insulin secretion in patients with type 2 diabetes (T2D); however, the results of various experimental studies do not support this notion. To address this discrepancy, we assessed the short- and long-term effects of hypomagnesemia on β-cell function and insulin secretion in primary mouse islets of Langerhans and in a mouse model of hypomagnesemia known asTrpm6Δ17 /fl;Villin1-Cremice. We found that lowering the extracellular Mg2+concentration from 1.2 mM to either 0.6 or 0.1 mM remarkably increased glucose-induced insulin secretion (GIIS) in primary islets isolated from C57BL/6 mice. Similarly, both the plasma insulin levels and GIIS rose in isolated islets ofTrpm6Δ17 /fl;Villin1-Cremice. We attribute these rises to augmented increases in intracellular Ca2+oscillations in pancreatic β-cells. However, the glycemic metabolic profile was not impaired inTrpm6Δ17 /fl;Villin1-Cremice, suggesting that chronic hypomagnesemia does not lead to insulin resistance. Collectively, the results of this study suggest that neither acute nor chronic Mg2+deficiency suppresses glucose-induced rises in insulin secretion. Even though hypomagnesemia can be symptomatic of T2D, such deficiency may not account for declines in insulin release in this disease.