A driving tool which is configured to drive a fastener supplied to a nose by using a striking mechanism which is operated by a fluid to be supplied, the driving tool comprising: a trigger that is configured to receive a manipulation which operates the striking mechanism; a contact arm that is configured to receive another manipulation which operates the striking mechanism; a contact lever that is configured to operate according to operations of the trigger and the contact arm and that is configured to switch operating states of the striking mechanism; and a regulator that is configured to switch operating states of the contact lever according to the contact arm, wherein the regulator includes: a regulation member that is configured to regulate a position of the contact lever at an operation standby position where the contact lever is operated by the contact arm; a moving member configured to move the regulation member; and a controller that is configured to control a movement of the moving member and to operate the regulation member, and the controller includes: a first cylinder that is configured to operate the regulation member, the first cylinder including a first piston that is movable, a first spring that presses the first piston, and a cylinder shaft that couples the first piston and the moving member; a second cylinder including a second piston that is movable, a second spring that presses the second piston; the driving tool being characterised by a check valve that is configured to suppress backflow of an air from the first cylinder to the second cylinder, wherein a fluid operating the striking mechanism is partially supplied to the second cylinder which is configured to generate a driving force for driving the first cylinder, and wherein a compressed fluid by movement of the second piston is supplied to the first cylinder. a trigger that is configured to receive a manipulation which operates the striking mechanism; a contact arm that is configured to receive another manipulation which operates the striking mechanism; a contact lever that is configured to operate according to operations of the trigger and the contact arm and that is configured to switch operating states of the striking mechanism; and a regulator that is configured to switch operating states of the contact lever according to the contact arm, wherein the regulator includes: a regulation member that is configured to regulate a position of the contact lever at an operation standby position where the contact lever is operated by the contact arm; a moving member configured to move the regulation member; and a controller that is configured to control a movement of the moving member and to operate the regulation member, and a regulation member that is configured to regulate a position of the contact lever at an operation standby position where the contact lever is operated by the contact arm; a moving member configured to move the regulation member; and a controller that is configured to control a movement of the moving member and to operate the regulation member, and the controller includes: a first cylinder that is configured to operate the regulation member, the first cylinder including a first piston that is movable, a first spring that presses the first piston, and a cylinder shaft that couples the first piston and the moving member; a second cylinder including a second piston that is movable, a second spring that presses the second piston; the driving tool being characterised by a check valve that is configured to suppress backflow of an air from the first cylinder to the second cylinder, wherein a fluid operating the striking mechanism is partially supplied to the second cylinder which is configured to generate a driving force for driving the first cylinder, and wherein a compressed fluid by movement of the second piston is supplied to the first cylinder. a first cylinder that is configured to operate the regulation member, the first cylinder including a first piston that is movable, a first spring that presses the first piston, and a cylinder shaft that couples the first piston and the moving member; a second cylinder including a second piston that is movable, a second spring that presses the second piston; the driving tool being characterised by a check valve that is configured to suppress backflow of an air from the first cylinder to the second cylinder, wherein a fluid operating the striking mechanism is partially supplied to the second cylinder which is configured to generate a driving force for driving the first cylinder, and wherein a compressed fluid by movement of the second piston is supplied to the first cylinder.