A work vehicle including an engine mounted on a traveling body including a traveling wheel (3, 4), a hydraulic stepless transmission mechanism that shifts a speed of a driving force from the engine, a gear shift pedal that performs an acceleration/deceleration operation of a shifted output from the hydraulic stepless transmission mechanism, and a control section that controls the engine and the hydraulic stepless transmission mechanism based on an operation amount of the gear shift pedal, the work vehicle being capable of performing an auto-cruise mode of keeping a vehicle speed constant, the work vehicle comprising: a cruise switch for setting whether to shift to the auto-cruise mode or not; and a set switch for shifting to the auto-cruise mode, wherein the control section shifts to an auto-cruise standby mode in which a shift to the auto-cruise mode is permitted when an on-operation on the cruise switch is received in a normal operation mode, and stores a vehicle speed and the number of revolutions of the engine in accordance with a foot operation position of the gear shift pedal and shifts to the auto-cruise mode when an operation on the set switch is received in a state where the gear shift pedal is pressed by the foot operation in the auto-cruise standby mode; the work vehicle comprising: an acceleration/deceleration switch that increases and reduces a vehicle speed in performing the auto-cruise mode, wherein when the control section receives an operation on the acceleration/deceleration switch in the auto-cruise mode, the control section is configured to increase and to reduce the vehicle speed stored in shifting to the auto-cruise mode and then keeps the vehicle speed constant; characterized by an accelerator cooperation switch configured to perform accelerator cooperation control of changing a vehicle speed in accordance with a pressing amount of the gear shift pedal and changing the number of revolutions of the engine, wherein in a case of shifting to the auto-cruise mode in performing the accelerator cooperation control, when the control section receives an operation on the acceleration/deceleration switch, the control section is configured to increase and to reduce the vehicle speed and the number of revolutions of the engine stored in shifting to the auto-cruise mode. a cruise switch for setting whether to shift to the auto-cruise mode or not; and a set switch for shifting to the auto-cruise mode, wherein the control section shifts to an auto-cruise standby mode in which a shift to the auto-cruise mode is permitted when an on-operation on the cruise switch is received in a normal operation mode, and stores a vehicle speed and the number of revolutions of the engine in accordance with a foot operation position of the gear shift pedal and shifts to the auto-cruise mode when an operation on the set switch is received in a state where the gear shift pedal is pressed by the foot operation in the auto-cruise standby mode; shifts to an auto-cruise standby mode in which a shift to the auto-cruise mode is permitted when an on-operation on the cruise switch is received in a normal operation mode, and stores a vehicle speed and the number of revolutions of the engine in accordance with a foot operation position of the gear shift pedal and shifts to the auto-cruise mode when an operation on the set switch is received in a state where the gear shift pedal is pressed by the foot operation in the auto-cruise standby mode; the work vehicle comprising: an acceleration/deceleration switch that increases and reduces a vehicle speed in performing the auto-cruise mode, wherein when the control section receives an operation on the acceleration/deceleration switch in the auto-cruise mode, the control section is configured to increase and to reduce the vehicle speed stored in shifting to the auto-cruise mode and then keeps the vehicle speed constant; an acceleration/deceleration switch that increases and reduces a vehicle speed in performing the auto-cruise mode, wherein when the control section receives an operation on the acceleration/deceleration switch in the auto-cruise mode, the control section is configured to increase and to reduce the vehicle speed stored in shifting to the auto-cruise mode and then keeps the vehicle speed constant; characterized by an accelerator cooperation switch configured to perform accelerator cooperation control of changing a vehicle speed in accordance with a pressing amount of the gear shift pedal and changing the number of revolutions of the engine, wherein in a case of shifting to the auto-cruise mode in performing the accelerator cooperation control, when the control section receives an operation on the acceleration/deceleration switch, the control section is configured to increase and to reduce the vehicle speed and the number of revolutions of the engine stored in shifting to the auto-cruise mode.