A double-seat valve has a seat-cleaning function and ensures that the seat-cleaning flow is conducted into and out of the leakage hollow space with as little turbulence as possible. The valve reliably prevents a pressure-increasing direct action upon the seat regions, even in the event that the cross-sectional area of the drain bore is smaller than that of the largest pipeline that can be connected to the valve. This is achieved in that a region of extension of the deflection surface that faces away from the radially outer end of the deflection surface delimits the remaining region of the opening in its entirety and opens out from the second closing element at an end-face and radially inner end of the second closing element, facing the first closing element.