PROBLEM TO BE SOLVED: To reduce a labor of a driver while suppressing reduction of work efficiency and waste fuel consumption.SOLUTION: A direction control part 60M performs automatic direct advance control for making a vehicle body travel on a target direct advance path on the basis of a positioning result of a positioning unit 86 in a control object area of the target direct advance path. A work control part 60G performs non-work state switching control for switching a state of a grounding work device to a non-work state in shift detection of the vehicle body from a direct advance state to a turnaround state by a shift detection part 70, and performs work state switching control for switching the state of a grounding work device A to a work state, in shift detection of the vehicle body from the turnaround state to the direct advance state by the shift detection part 70. An engine control part 60H performs engine temporary stop control in establishment of a temporary stop condition, and performs engine re-start control in establishment of a re-start condition. The direction control part 60M stops the automatic direct advance control in execution of the engine temporary stop control during the automatic direct advance control, and restarts the automatic direct advance control in execution of the engine re-start control during stop of the automatic direct advance control.SELECTED DRAWING: Figure 6【課題】作業効率の低下、無駄な燃料消費を抑制しながら、運転者の労力を軽減する。【解決手段】方向制御部６０Ｍは、目標直進経路の制御対象領域では、測位ユニット８６の測位結果などに基づいて車体を目標直進経路上で走行させる自動直進制御を行い、作業制御部６０Ｇは、推移検出部７０による車体の直進状態から方向転換状態への移行検出で対地作業装置を非作業状態に切り替える非作業状態切り替え制御を行い、推移検出部７０による車体の方向転換状態から直進状態への移行検出で対地作業装置Ａを作業状態に切り替える作業状態切り替え制御を行い、エンジン制御部６０Ｈは、一時停止条件の成立でエンジン一時停止制御を行い、再始動条件の成立でエンジン再始動制御を行い、方向制御部６０Ｍは、自動直進制御中でのエンジン一時停止制御の実行で自動直進制御を中断し、かつ、自動直進制御の中断中でのエンジン再始動制御の実行で自動直進制御を再開する。【選択図】図６
