Temperature control system

A temperature control system includes a battery; a power electronics device that converts high-voltage electric power; an air passage; an inside-air intake passage and an outside-air intake passage that acquire inside air and outside air of a vehicle, and supply the airs to the air passage; an intake opening/closing member that opens and closes between the air passage and each of the intake passages; a passage switch that switches among a power-electronics prioritized state, a battery prioritized state, and a retention state; and a control device including a processor and a memory coupled to the processor. In a state in which a temperature of the outside air is lower than a battery lower limit temperature, the processor performs switching control of a power-electronics prioritized state, a battery prioritized state, and a retention state with the passage switches, based on an output value of the power electronics device.