Provided is an engine cooling device in which a flow passage switching part, which is provided between an outlet (EFb) of a cooling flow passage (EF) and a radiator and between the outlet (EFb) of the cooling flow passage (EF) and a pump, has valves that perform switching to a radiator connection flow passage or a bypass flow passage according to a temperature of a coolant (W), and a sleeve that is connected in parallel to the valves and is configured to circulate the coolant (W) to both the bypass flow passage and the radiator connection flow passage.