PROBLEM TO BE SOLVED: To provide a method for manufacturing a composite material capable of stably and efficiently manufacturing the composite material having a part to be detected in a predetermined position.SOLUTION: In the method for manufacturing the composite material in which the composite materials 3 having the detected part in the predetermined position are manufactured by cutting a continuous body 30 on which parts to be detected by a sensor are intermittently arranged in a flow direction, a start-up operation in which the conveying speed of the continuous body 30 is increased a targeted conveying speed while controlling the conveying speed of the continuous body 30 based on the position of dancer 63 in contact with the continuous body is performed prior to a steady operation in which the composite materials are manufactured while detecting the part to be detected during the conveyance of the continuous body 30 and controlling an alignment so that a cutting position of the continuous body and the position of a part to be detected may fill a prescribed relation.
