The invention relates to a gas detecting and reusing integrated device for electrical SF6 equipment and a reusing method of the gas detecting and reusing integrated device. The bottom of the electrical SF6 equipment is provided with an SF6 gas charging and discharging valve. The gas detecting and reusing integrated device comprises an SF6 gas detecting device, an SF6 gas charging and discharging pipe, an SF6 gas reusing treatment device and a tail gas discharging pipe; one end of the SF6 gas charging and discharging pipe is communicated with the SF6 gas charging and discharging valve, and the other end of the SF6 gas charging and discharging pipe is communicated with an SF6 gas detector; the gas detecting device comprises a compression pump, a vacuum pump, a drying pipe, a first purifying pipe, a second purifier and a gas storage tank, wherein the vacuum pump, the drying pipe, the first purifying pipe and the second purifier are communicated with the compression pump; one end of the tail gas discharging pipe is connected with a gas discharging port of the SF6 gas detector in a sealing mode, the other end of the tail gas discharging pipe is communicated with the drying pipe, an outlet of the gas storage tank is communicated with an inlet of the vacuum pump, and an outlet of the compression pump is communicated with the SF6 gas charging and discharging pipe through a compression pump outlet pipe. The gas detecting and reusing integrated device has the advantages that SF6 gas obtained after detecting not only can be recycled and purified, but also can be reused on line, and therefore safe operation of the electrical SF6 equipment is powerfully guaranteed.