De Gea has been strongly linked with a move to Spanish giants Real Madrid this summer.
Reports in Spain suggest that Real Madrid will make one last attempt to sign the goalkeeper before the transfer window closes.
But Van Gaal insists that United have no plans of selling their highly-rated goalkeeper.
Van Gaal said today: “I think when Manchester United wants a player he shall come, besides when a club is not selling. It is the same with us. We are not selling De Gea.”