To accurately perform adjustment of an application amount even when it is difficult to adjust an application amount due to that there are uneven surfaces and ill-drained paddy fields in a farm field, and a real travel speed is unstable.SOLUTION: A work vehicle is provided with a fertilizer application controller 12A for controlling a delivery device 8 of a tank 7 loaded on a machine body which travels with front and rear wheels 4,5. The work vehicle is configured such that: a speed detection signal from an axle rotation sensor 45 provided in a driving system of the front and rear wheels 4,5, and a GPS speed sensor 46 for detecting a travel speed by a position signal from a GPS satellite is input into the fertilizer application controller 12A； a delivery amount of the delivery device 8 is automatically controlled by an average value of both speed signals； and an abnormality alarm is output when any one of the axle rotation sensor 45 and the GPS speed sensor 46 detects a speed of zero.SELECTED DRAWING: Figure 10【課題】圃場には凹凸面や湿田があって実走行速度が不安定で散布量の調整が難しい場合でも、散布量の調整を正確に行う。【解決手段】前後車輪４，５で走行する機体に搭載したタンク７の繰出装置８を制御する施肥コントローラ１２Ａを設けた作業車両であって、前記前後車輪４，５の駆動系に設ける車軸回転センサ４５とＧＰＳ衛星からの位置信号で走行速度を検出するＧＰＳ速度センサ４６からの速度検出信号を前記施肥コントローラ１２Ａに入力し、両速度信号の平均値で繰出装置８の操出量を自動制御すると共に、前記車軸回転センサ４５と前記ＧＰＳ速度センサ４６の何れか一方が速度ゼロを検出すると異常警報を出力することを特徴とする作業車両とする。【選択図】図１０
