A controller of a thermal management system for a vehicle controls a first switching valve and a second switching valve to set a battery warming-up state in which a heat medium circulates between a battery-temperature adjustment heat exchanger and a heat-medium heating heat exchanger, and the heat medium does not circulate between a coolant-coolant heat exchanger and a heat-medium heating heat exchanger when both a battery and an engine need to be warmed up. In contrast, the controller controls the first switching valve and the second switching valve to set an engine warming-up state in which the heat medium circulates through between the coolant-coolant heat exchanger and the heat-medium heating heat exchanger while the heat medium does not circulate between a battery-temperature adjustment heat exchanger and the heat-medium heating heat exchanger when a temperature of the battery exceeds a target battery warming-up temperature in the battery warming-up state.