A thermal management system includes: a first radiator, a first electric water pump, and a first coolant line configured to allow a coolant to be circulated by the first electric water pump; a second radiator, a second electric water pump, and a second coolant line configured to allow a coolant to be circulated by the second electric water pump; and a first flow control device and a second flow control device installed at front ends and rear ends of the first radiator and the second radiator so as to control a coolant flow direction between the first coolant line, the second coolant line, and a third coolant line. The third coolant line is installed so as to connect the first flow control device and the second flow control device to each other.