A valve for a vehicle provided between a transmission and an oil cooler for cooling transmission oil may include a valve housing in which a first inflow port connected to the transmission and an exhaust port connected to the oil cooler are formed on both sides facing each other and a bypass port connected to the transmission and a second inflow port connected to the oil cooler are formed at a position spaced apart from the first inflow port and the exhaust port along a length direction of the valve housing, and a control unit that is mounted inside the valve housing, selectively connects the first inflow port to the exhaust port or the bypass port while expansion or contraction is performed depending on a temperature of the transmission oil, and selectively closes the exhaust port to control a flow stream of the transmission oil.