A temperature-controllable gas grill includes a base, a cover, a gas valve, several burners, and a temperature controlling device. The cover is provided on the base to form a grilling chamber between the base and the cover. The gas valve is connected to the gas pipe. The burners are provided in the base and are connected to the gas valve. The temperature controlling device includes a gas controller, a temperature sensor, and a main controller. The temperature sensor senses a temperature in the grilling chamber and provides a temperature signal accordingly. The main controller is electrically connected to the temperature sensor to receive the temperature signal. The main controller changes a gas flow supplied to the burners according to the temperature signal to control the temperature in the grilling chamber to control the temperature in the grilling chamber.