The embroidery device of the invention comprises an embroidery case provided with a drive unit. The drive unit can drive an embroidery needle below the embroidery case. The lower part of the embroidery case is connected to at lest two tape spool seats, and each tape spool seat is provided with a tape spool for the winding of feed belt. The tape spool can freely rotated, and the embroidery device is also provided with a guide mouth for the guiding of the feed belt. With the application of the mechanical embroidery method of the embroidery device and in accordance with a computer embroidery program, at lest two embroidery feed belts installed on the tape spool is synchronously output through the guide mouth. Moreover through the reciprocating action of the embroidery needle, the output feedbelt is connected to the embroidered cloth through an embroidery line. With the embroidery device and the mechanical embroidery method of the invention, double or multiple winding strings, strings, string with beads or other materials can be synchronously output and embroidered on the embroidered cloth. Therefore, the combination conditions of materials are expanded, and the diversity of embroidery patterns is achieved.