PURPOSE: To reduce a cost and improve positioning accuracy of a carriage workpiece, by using in common a flow control valve in a control method of fluid actuator of positioning a positioning control object in a target position, in cut in control of a cutting head and in positioning control of carriage workpiece by a carriage feed cylinder.

CONSTITUTION: In the case of positioning a positioning control object in a target position by a fluid actuator, controlling a speed of the fluid actuator by rotation controlling a motor connected to a flow control valve, flow control valve of controlling a cut in speed of cut in cylinder of performing cut in action of a cutting head 5 at cutting time of sawing machine 1 and a flow control valve of controlling a feed speed of carriage feed cylinders 55, 71 of performing carriage action of a workpiece W relating to a cutting position are used in common, to alternately perform control of cut in speed and control of a feed speed.