The invention provides a launching device for a single electrode producing low-temperature plasma flow under the atmospheric pressure condition. The launching device for the single electrode producing the low-temperature plasma flow under the atmospheric pressure condition comprises an air current device, a high-voltage power supply, a line electrode and a metal ball electrode. The air current device is composed of an air source, a flow meter, a shutoff valve and an air inlet pipe, wherein the air source, the flow meter, the shutoff valve and the air inlet pipe are connected in sequence through an air pipe. The launching device for the single electrode producing the low-temperature plasma under the atmospheric pressure condition is characterized in that one end of the line electrode is fixed on the metal ball electrode, the metal ball electrode is arranged at one end of a medium pipe and seals an end port of the medium pipe, the line electrode is arranged in the medium pipe and on the center of an axis, the other end of the line electrode is hung on the inner side of a spray nozzle of the medium pipe, the air inlet pipe is arranged on the medium pipe and is communicated with the medium pipe, the metal ball electrode is connected with the high-voltage output end of the high-voltage power supply through a guide wire, and the low-voltage end of the high-voltage power supply is connected with the ground. According to the launching device for the single electrode producing the low-temperature plasma flow under the atmospheric pressure condition, production and launching of the low-temperature plasma flow are achieved under the atmospheric pressure, spraying distance of the low-temperature plasma flow is effectively improved, the working environment is not limited to inert gases, and the industrial application prospect is wide.