A sewing machine includes a drive frame mounted on the table of the sewing machine and at least two Y-direction drive mechanisms arranged at a spacing in the right-and-left directions of the sewing machine for driving the drive frame in the back-and-forth directions of the dewing machine. The sewing machine includes an upper frame erected over the table. Each of the Y-direction drive mechanisms includes a rail mounted on the upper frame and extending in the back-and-forth directions of the sewing machine, a moving portion mounted on the rail slidably in the back-and-forth directions of the sewing machine and jointed to the drive frame, and a drive portion for driving the moving portion in the back-and-forth directions of the sewing machine.