The invention discloses a plant power generation device comprising a base, a plurality of pots, plants, solar panels and a power storage device. The pots are arranged on the base, the plants are planted in the pots and are mosses, the pots are made of conductive fibers, the solar panels are arranged on the periphery of the base in a manner of inclining at 45 degrees inward, and the pots and the solar panels are connected to the power storage device electrically. Thus, the plant power generation device has the advantages that in the process of releasing organic compounds, containing bacteria, and bacteria decomposition complexes to the soil through moss photosynthesis, electrons are produced and are captured and utilized by the conductive fibers, and solar energy is converted into power through the solar panels; the plant power generation device has promised market prospect for popularization.