The utility model discloses a gas tank heating device. The gas tank heating device is used for gasifying sulfur hexafluoride, and comprises an automobile power plug, an electric wire, an electric heating device, a temperature controller and a wrapping coat body, wherein one end of the electric wire is connected with the automobile power plug, and the other end of the electric wire is connected with the electric heating device; the temperature controller is arranged on the electric wire; the electric heating device is arranged on the wrapping coat body. When the gas tank heating device is used, the wrapping coat body wraps a gas tank filled with the sulfur hexafluoride, the automobile power plug is plugged in an automobile power supply, the heating temperature is controlled through the temperature controller, and the electric heating device produces heat after being electrified to heat the gas tank, so that heating can be realized on vehicle at any time and any place; when the sulfur hexafluoride is added outdoors, continuous heating can be realized, and the sulfur hexafluoride keeps in a gaseous state to guarantee normal operation.