The invention relates to a sulfur hexafluoride inflating device. The sulfur hexafluoride inflating device comprises a sulfur hexafluoride storage cylinder. The sulfur hexafluoride storage cylinder isprovided with a pressure reducing valve. The pressure reducing valve is connected with a gas filling pipe. The free end of the gas filling pipe is connected with a gas filling plug. The sulfur hexafluoride inflating device is characterized in that a distribution valve is connected between the gas filling pipes; the distribution valve is provided with a precise pressure meter and a safety valve; the sulfur hexafluoride storage cylinder is arranged in a heating sleeve; the sleeve wall of the heating sleeve is provided with an interlayer; an electric heating wire is arranged in the interlayer andis connected to a power supply through an electromagnetic relay; the electromagnetic relay is connected to a microcontroller; the input end of the microcontroller is connected with a temperature sensor; the temperature sensor is arranged on the inner wall of the heating sleeve.