PROBLEM TO BE SOLVED: To provide a working vehicle capable of maintaining the tillage depth constant in a headland etc.SOLUTION: The working vehicle comprises obtaining the rolling angular velocity of a traveling machine body in time series (S101); carrying out Fourier transformation with an angular velocity data for a prescribed time (S102); computing characteristic values of the rolling angular velocity in a prescribed frequency band (S103); when the characteristic values are not lower than the predetermined threshold value (S104:YES), determining that correction of the rolling angle of the working vehicle according to the extent of tire sinking is necessary (S105); and when the characteristic values are lower than the threshold value (S104:NO), determining that the correction is not necessary (S106).COPYRIGHT: (C)2009,JPO&INPIT【課題】枕地等において耕耘深さを一定に保つことを可能にする作業車両の提供。【解決手段】走行機体のローリング角速度を時系列的に取得し(S101)、所定時間分の角速度データでフーリエ変換を実施する(S102)。そして、所定周波数帯域でのローリング角速度の特性値を算出し(S103)、特性値が予め定めた閾値以上である場合(S104:YES)、作業機ローリング角度のタイヤ沈下量に応じた補正が必要と判定し(S105)、閾値未満の場合(S104:NO)、補正が不要と判定する(S106)。【選択図】図7