The invention relates to a gas carrying device of a transformer oil chromatography online monitoring system, and belongs to the field of electrical tests. The gas carrying device comprises a pressurecontroller, a press, a gas inlet filter, a gas storage chamber, an automatic liquid discharge valve, an overvoltage protector, a primary voltage stabilizer, an output end dryer, a hydrocarbon removalpurifier, a secondary voltage stabilizer, an air output port and an air inlet relay, wherein the gas inlet filter is connected with the press; the press is connected with the gas storage chamber; thegas storage chamber is connected with the output end dryer through the primary voltage stabilizer; the output end dryer is connected with the hydrocarbon removal purifier; the hydrocarbon removal purifier is connected with the air inlet relay through the secondary voltage stabilizer; the air inlet relay and the air output port are connected to a chromatography monitoring device. The gas carrying device has the functions of no maintenance and no gas cylinder, avoids the gas cylinder replacement period taking three months as the period, saves manpower, money and material resources, and greatly improves the power supply reliability.