A heat management system disclosed herein is used for an electric vehicle. The heat management system may include an oil cooler, an oil pump, a converter cooler, a first heat exchanger, a second heat exchanger, a first channel, a second channel, a channel valve, a bypass channel, and a controller. The channel valve may be configured to select a first valve position and a second valve position. The bypass channel may be configured to allow the first heat medium to bypass the first heat exchanger and circulate between the oil cooler and the converter cooler when the second valve position is selected. The controller may be configured to control the channel valve such that the channel valve selects the first valve position and activate the oil pump in response to the temperature of the first heat medium in the first channel becoming higher than a predetermined upper limit temperature.