A working vehicle comprising: a traveling clutch configured to be switched between: an engaging state allowing power to be transmitted to a traveling device; and a disengaging state cutting the power to be transmitted to the traveling device; a braking device (46a, 46b) configured to brake the traveling device according to operation of a braking-operation member; a controller device configured to perform: a braking control to perform the braking according to the operation of the braking-operation member; and an auto-switching control to switch the traveling clutch from the engaging state to the disengaging state according to the operation of the braking-operation member; and a switching member configured to switch the auto-switching control between to be valid and to be invalid, wherein the controller device is configured to perform: a first processing to switch the traveling clutch from the engaging state to the disengaging state when the braking-operation member is operated in a case where the auto-switching control is valid and a vehicle speed of the traveling device is less than a threshold; and a second processing to prevent the traveling clutch from being switched from the engaging state to the disengaging state even when the braking-operation member is operated in a case where the vehicle speed of the traveling device is equal to or higher than the threshold, characterized in that the working vehicle comprises: an operator seat; and a sitting detector sensor configured to detect whether an operator is sitting on the operator seat, wherein the controller device is configured to hold the traveling clutch in the disengaging state when the sitting detector sensor does not detect that the operator is sitting on the operator seat after the first processing. a traveling clutch configured to be switched between: an engaging state allowing power to be transmitted to a traveling device; and a disengaging state cutting the power to be transmitted to the traveling device; an engaging state allowing power to be transmitted to a traveling device; and a disengaging state cutting the power to be transmitted to the traveling device; a braking device (46a, 46b) configured to brake the traveling device according to operation of a braking-operation member; a controller device configured to perform: a braking control to perform the braking according to the operation of the braking-operation member; and an auto-switching control to switch the traveling clutch from the engaging state to the disengaging state according to the operation of the braking-operation member; and a braking control to perform the braking according to the operation of the braking-operation member; and an auto-switching control to switch the traveling clutch from the engaging state to the disengaging state according to the operation of the braking-operation member; and a switching member configured to switch the auto-switching control between to be valid and to be invalid, wherein the controller device is configured to perform: a first processing to switch the traveling clutch from the engaging state to the disengaging state when the braking-operation member is operated in a case where the auto-switching control is valid and a vehicle speed of the traveling device is less than a threshold; and a second processing to prevent the traveling clutch from being switched from the engaging state to the disengaging state even when the braking-operation member is operated in a case where the vehicle speed of the traveling device is equal to or higher than the threshold, a first processing to switch the traveling clutch from the engaging state to the disengaging state when the braking-operation member is operated in a case where the auto-switching control is valid and a vehicle speed of the traveling device is less than a threshold; and a second processing to prevent the traveling clutch from being switched from the engaging state to the disengaging state even when the braking-operation member is operated in a case where the vehicle speed of the traveling device is equal to or higher than the threshold, characterized in that the working vehicle comprises: an operator seat; and a sitting detector sensor configured to detect whether an operator is sitting on the operator seat, wherein the controller device is configured to hold the traveling clutch in the disengaging state when the sitting detector sensor does not detect that the operator is sitting on the operator seat after the first processing. an operator seat; and a sitting detector sensor configured to detect whether an operator is sitting on the operator seat, wherein the controller device is configured to hold the traveling clutch in the disengaging state when the sitting detector sensor does not detect that the operator is sitting on the operator seat after the first processing.