PURPOSE: To reduce labors when materials of tatami mats are cut and sewed.

CONSTITUTION: Cutters 2A, 2B which cut a tatami floor breadthwise and cut both tatami floor and front cover thereof at the same time lengthwise and a sewing machine 3 which sews the front cover on the tatami floor or sews the tatami edges on the tatami floor and the front cover, are installed on a base frame 1 and a computer controller 4 for the automatic control of the cutters 2A, 2B and the sewing machine 3 is attached thereto. In this time, specified measured information regarding the strain of the floor face of a room is input in the computer and operations to assign the strain to a preset number of tatami mat on the basis of the information are carried out. The operated result is stored as a control information and a specified actuating instruction is input to automatically operate the cutters 2A, 2B and the sewing machine 3 on the basis of the control information.