Provided is a structure for connecting a combustor (3), which generates a combustion gas inside cylinders (33), to a turbine unit (4), which generates a rotational motive force by sequentially passing the combustion gas through turbine stages comprising turbine stator vanes (4SV) and turbine rotor blades. At least part of the one-stage turbine stator vane (4SV) closest to the combustor (3) is disposed downstream of side walls (34) in one cylinder (33) and another cylinder (33) adjacent thereto. The distance from the leading edge of the one-stage turbine stator vane (4SV) disposed downstream of the side wall (34) in the cylinder (33) to the turbine unit (4) end of the side wall (34) is less than or equal to the spacing between the inner surface of the side wall (34) of the one cylinder (33) to the inner surface of the side wall (34) of the other cylinder (33).