Many approaches have shown beneficial effects of modified mesenchymal stem cells (MSCs) for treatment of infarcted myocardium, but have primarily focused on enhancing the survival of transplanted MSCs. Here, we show the dual benefits of periostin-overexpressing MSCs (p-MSCs) for infarcted myocardium. P-MSCs led to the marked histological and functional recovery of infarcted myocardium by enhancing survival of MSCs and directly preventing apoptosis of cardiomyocytes. Survival of p-MSCs themselves and cardiomyocytes co-cultured with p-MSCs or treated with the conditioned media from p-MSCs was significantly increased under hypoxic conditions. Decreases in adhesion-related integrins were reversed in cardiomyocytes co-cultured with p-MSCs, followed by increases in p-PI3K and Akt, indicating that periostin activates the PI3K pathway through adhesion-related integrins. When p-MSCs were injected into myocardial infarcted rats, histological pathology and cardiac function were significantly improved compared to MSC-injected controls. Thus, periostin might be a new target of therapeutic treatments using MSCs as carriers for infarcted myocardium.