A work vehicle including: a lower travel structure; an upper swing structure; a front work device; a diesel engine; an exhaust gas cleaning system including: a filtering unit disposed in an exhaust system of the engine, the filtering unit including a filter for collecting particulate matter included in an exhaust gas; and regeneration units (40, 50) for increasing the temperature of the exhaust gas to burn off and remove particulate matter deposited in the filter; a main hydraulic pump being driven by the motive power of the engine; a plurality of hydraulic actuators comprising travelling motors (104a, 104b), a swing motor (13, 105), and hydraulic cylinders (14, 15, 114, 115, 116) driven by pressure oil discharged from the main hydraulic pump; a plurality of flow control valves (17, 18, 19) for controlling a flow of the pressurized oil supplied from the hydraulic pump to the plurality of hydraulic actuators; a plurality of first operation means (25, 26, 27) disposed in a cabin provided to the upper swing structure for generating control pilot pressures for operating the plurality of flow control valves; characterised in that it further comprises: second operation means comprising a gate lock lever that is selectively operated between a first position at which an entrance of a driver's seat in the cabin is shut and the control pilot pressures can be generated by the first operation means to enable operation of the plurality of flow control valves thereby to enable all operation of the plurality of hydraulic actuators for driving the lower travel structure, the upper swing structure and the front work device and a second position at which the entrance of the driver's seat is opened and the control pilot pressures cannot be generated by the plurality of first operation means to disable all operation of the plurality of flow control valves thereby to disable the operation of the plurality of hydraulic actuators for driving the lower travel structure, the upper swing structure and the front work device; and third operation means disposed in the cabin for instructing start of the operation of the regeneration units (40, 50); and a regeneration control unit (41, 41A) for starting the operation of the regeneration units (40, 50), when the gate lock lever is switched to the second position at which the entrance of the driver's seat is opened while the all operation of the plurality of hydraulic actuators is disabled, and in this state when the third operation means is operated to instruct the start of the operation of the regeneration units (40, 50). a lower travel structure; an upper swing structure; a front work device; a diesel engine; second operation means comprising a gate lock lever that is selectively operated between a first position at which an entrance of a driver's seat in the cabin is shut and the control pilot pressures can be generated by the first operation means to enable operation of the plurality of flow control valves thereby to enable all operation of the plurality of hydraulic actuators for driving the lower travel structure, the upper swing structure and the front work device and a second position at which the entrance of the driver's seat is opened and the control pilot pressures cannot be generated by the plurality of first operation means to disable all operation of the plurality of flow control valves thereby to disable the operation of the plurality of hydraulic actuators for driving the lower travel structure, the upper swing structure and the front work device; and third operation means disposed in the cabin for instructing start of the operation of the regeneration units (40, 50); and a regeneration control unit (41, 41A) for starting the operation of the regeneration units (40, 50), when the gate lock lever is switched to the second position at which the entrance of the driver's seat is opened while the all operation of the plurality of hydraulic actuators is disabled, and in this state when the third operation means is operated to instruct the start of the operation of the regeneration units (40, 50).