Our previous study demonstrated that zinc prevents cardiac reperfusion injury by targeting the mitochondrial permeability transition pore (mPTP) via Akt and glycogen synthase kinase 3 (GSK-3). We aimed to address the mechanism by which zinc activates Akt. Treatment of H9c2 cells with ZnCl2 (10 µM) for 20 min enhanced Akt phosphorylation (Ser473), indicating that zinc can rapidly activate Akt. Zinc did not alter either PTEN (phosphatase and tensin homolog on chromosome ten) phosphorylation and total PTEN protein levels or PTEN oxidation, implying that PTEN may not play a role in the action of zinc. However, zinc-induced Akt phosphorylation was blocked by both the non-selective receptor tyrosine kinase (RTK) inhibitor genistein and the selective insulin-like growth factor-1 RTK (IGF-1RTK) inhibitor AG1024, indicating that zinc activates Akt via IGF-1RTK. Zinc-induced phosphorylation of protein tyrosine and serine/threonine was also abolished by AG1024. In addition, zinc markedly enhanced phosphorylation of IGF-1R, which was again reversed by genistein and AG1024. Confocal imaging study revealed that AG1024 abolished the preventive effect of zinc on oxidant-induced mPTP opening, confirming that IGF-1RTK plays a role in zinc-induced cardioprotection. Furthermore, zinc decreased the activity of protein phosphatase 2A (PP2A), a major protein serine/threonine (Ser/Thr) phosphatase, implying that protein Ser/Thr phosphatases may also play a role in the action of zinc on Akt activity. Taken together, exogenous zinc activates Akt via IGF-1RTK and prevents the mPTP opening in cardiac cells. Inactivation of Ser/Thr protein phosphatases may also contribute to zinc-induced Akt activation.