A temperature regulator is provided for a battery which includes an electrode body, a terminal electrically connected to the electrode body, and a casing that receives the electrode body and supports the terminal with an end portion of the terminal protruding outside of the casing. The casing is electrically and thermally insulated from the terminal. The temperature regulator includes a flow producer, a temperature sensor, and a controller. The flow producer produces a flow of a heat transfer medium for exchanging heat between the heat transfer medium and one of the terminal and casing. The temperature sensor senses the temperature of the other of the terminal and casing. The controller controls, based on the temperature sensed by the temperature sensor, the flow producer to adjust the flow rate of the heat transfer medium, thereby regulating the temperature of the electrode body to fall within a predetermined range.