A hydraulic system includes: a boom cylinder to move a boom; a working tool cylinder to move a working tool attached to the boom; a boom control valve to control the boom cylinder; a working tool control valve to control the working tool cylinder; a horizontal control valve having: an activating position to allow a horizontalizing operation of the working tool; and a stopping position to stop the horizontalizing operation; and a controller device having: a first information obtaining portion to obtain permission and non-permission to the horizontalizing operation; a second information obtaining portion to obtain at least one of upward operation and upward movement of the boom; and a horizontal controller to set the horizontal control valve to the stopping position when the first information obtaining portion obtains the non-permission and the second information obtaining portion obtains one of the upward operation and the upward movement.