A ride-on rice-planting machine having an engine (5), a steering wheel body (15) provided behind the engine (5), and an operation panel body (10) for covering over the engine (5), wherein the presence of the operation panel body (10) over the engine (5) does not hinder maintenance of the upper part etc. of the engine (5). An upper shaft (41) of the steering wheel body (15) is constructed so that it can vertically pivot about a laterally placed tilt shaft (46) in a manner approaching and moving away from the operation panel body (10). The operation panel body (10) is constructed so that it can vertically pivot about a tubular shaft section (65) as a lateral support shaft installed in parallel with the tilt shaft (46) of a pivotable frame (61), and when the operation panel body (10) is pivoted, it is opened and closed in a manner approaching and moving away from the steering wheel body (15). The upper shaft (41) and the operation panel body (10) can pivot independently from each other.
