The invention relates to a device for recycling drain water of a power plant low-pressure heating steam pipeline. The device comprises a drain water collecting pipe, a plurality of drain water ports are formed in a pipe body of the drain water collecting pipe, a drain water collecting pipe plug is mounted at a pipe opening of one end of the drain water collecting pipe, and a pipe opening of the other end of the drain water collecting pipe communicates with a drain water storing tank; the drain water storing tank communicates with one end of an exhausting pipeline, and the other end of the exhausting pipeline serves as an exhausting opening; and a water discharging opening is formed in the drain water storing tank, and a liquidometer port, a thermometer port and temperature indicator lightsare disposed on the drain water storing tank separately. By means of the device, the drain water of the heating pipeline in a plant can be recycled effectively, the situation that the drain water isdischarged into a collecting pipe of a drain water expander of an original set, and consequently the vacuum tightness of the set is affected is avoided, mist all around in the plant due to discharging into a non-pressure water discharging pipeline and the potential safety hazards caused by discharging from pressed drain water to non-pressure water discharging are eliminated, and the running safety of the power plant low-pressure heating steam pipeline can be guaranteed.