Array substrate and electronic paper display device

The invention discloses an array substrate and an electronic paper display device. The array substrate comprises a substrate; the plurality of grid lines and the plurality of data lines are arranged on the substrate base plate, the plurality of grid lines and the plurality of data lines are arranged in a crossed mode, and a plurality of pixel areas are defined; the thin film transistor and the first electrode are located in the pixel area, a grid electrode of the thin film transistor is electrically connected with the corresponding grid line, and a drain electrode of the thin film transistor is electrically connected with the first electrode; a source electrode of the thin film transistor comprises a first conductive part and a second conductive part electrically connected between the first conductive part and a corresponding data line, and the orthographic projection of the first conductive part and the orthographic projection of the second conductive part on the substrate body are overlapped with the orthographic projection of the first electrode on the substrate body. And the size of the second conductive part in the extending direction of the data line is smaller than that of the first conductive part in the extending direction of the data line.