The invention provides a gas-phase ethane pipeline discharged air recycling technology and device. The device comprises a valve, a compressor, an air cooler, a condenser, a storage cabinet, a pressuregauge, a thermometer and a flow meter. The compressor can provide pressure for discharged air, and over-station recycling of the discharged air is realized. The condenser can be used for liquefying the air, so that recycling of the discharged air through the storage cabinet is achieved. The air cooler can control the outlet temperature of the compressor, and the damage of the high temperature toa recycling pipeline and an anti-corrosion layer of a downstream conventional conveying pipeline is effectively reduced. The thermometer, the pressure gauge and the flow meter can monitor the temperature, pressure and flow of the recycling process, and then the recycling progress is controlled. The technology and device solve the problem that an existing conventional pipeline recycling technologyand device cannot recycle gas-phase ethane pipeline discharged air which is prone to gas-liquid phase change and high in economical efficiency, and have the advantages of being safe to operate and high in recycling economical efficiency.