Seat of coach

The utility model relates to a seat, in particular to a seat of a coach. The seat of the coach comprises a backrest, a first seat surface and a supporting leg, wherein the first seat surface is support on a floor in the coach through the supporting leg; the backrest is connected with the first seat surface through a backrest adjustable mechanism; an arc-shaped projection is arranged on the lower portion of the front of the backrest; a transitional section is arranged at a butted portion of the backrest and the first seat surface and comprises a first inner arc surface and a second inner arc surface; the first inner arc surface and the first seat surface are in transition gradually; a portion, which is in butt joint with the backrest, of the first seat surface is a third arc surface; and the second inner arc surface is in butt joint with the third arc surface. Moreover, another seat surface is arranged at the outer end of the first seat surface, so that the two seat surfaces are combined, the width of the firs