A damper operation control device of a working vehicle, includes: a boom pivotably supported on a vehicle body; a bucket pivotably supported on a tip end of the boom; a lift cylinder which drives the boom; an accumulator connected to the lift cylinder through a branched oil passage; a switching valve connected to the branched oil passage between the lift cylinder and the accumulator, the switching valve switching between a connected state and a disconnected state between the lift cylinder and the accumulator; and a controller which performs switch control of the switching valve, wherein the controller includes: a state detecting unit which detects whether the bucket is in a loaded state; and a switching valve control unit which switches the switching valve to the connected state when the state detecting unit detects that the bucket is in the loaded state.