A gas turbine comprising: a combustor which is configured to inject a fuel into compressed air to burn the fuel; an upstream side member (23;38,39;43,44) facing a passage of a gas main stream, the upstream side member (23;38,39;43,44) being downstream of the combustor; and a downstream side member (43,44;38,39) disposed downstream from the upstream side member (23;38,39;43,44) to define a cavity (C1-C8) with the upstream side member (23; 38, 39; 43, 44); wherein the upstream side member (23;38,39;43,44) includes a cavity inner wall portion (23b;38h,39h;43h,44h) of a downstream side end portion of the upstream side member (23;38,39;43,44), the cavity inner wall portion (23b;38h,39h;43h,44h) facing the cavity (C1-C8) so as to form an inner wall of the cavity (C1-C8), and a wall portion (23c;38f,39f;43f,44f) which is an end face of a downstream side of the upstream side member (23; 38, 39; 43, 44), wherein the downstream side member (43,44;38,39) includes a guide face (43c,44c;38c,39c) facing the passage and having a concave shape surface arranged in the passage side as the guide face (43c,44c;38c,39c) goes toward the upstream side, wherein, when viewed in a cross section in which the upstream side member (23;38,39;43,44) and the downstream side member (43,44;38,39) are cut along a rotor shaft (Ar), an upstream side end portion of the guide face (43c,44c;38c,39c) is formed such that a swirling current flows along the guide face (43c,44c;38c,39c) and an extension section of the guide face (43c,44c;38c,39c) without colliding with the upstream side member (23;38,39;43,44), the extension section being a line extending from an upstream most end of the guide face (43c,44c;38c,39c) toward the upstream side in a direction parallel to a surface of the upstream end portion of the guide face (43c,44c;38c,39c), and wherein the extension section does not intersect with the upstream side member (23;38,39;43,44). a combustor which is configured to inject a fuel into compressed air to burn the fuel; an upstream side member (23;38,39;43,44) facing a passage of a gas main stream, the upstream side member (23;38,39;43,44) being downstream of the combustor; and a downstream side member (43,44;38,39) disposed downstream from the upstream side member (23;38,39;43,44) to define a cavity (C1-C8) with the upstream side member (23; 38, 39; 43, 44); wherein the upstream side member (23;38,39;43,44) includes a cavity inner wall portion (23b;38h,39h;43h,44h) of a downstream side end portion of the upstream side member (23;38,39;43,44), the cavity inner wall portion (23b;38h,39h;43h,44h) facing the cavity (C1-C8) so as to form an inner wall of the cavity (C1-C8), and a wall portion (23c;38f,39f;43f,44f) which is an end face of a downstream side of the upstream side member (23; 38, 39; 43, 44), a cavity inner wall portion (23b;38h,39h;43h,44h) of a downstream side end portion of the upstream side member (23;38,39;43,44), the cavity inner wall portion (23b;38h,39h;43h,44h) facing the cavity (C1-C8) so as to form an inner wall of the cavity (C1-C8), and a wall portion (23c;38f,39f;43f,44f) which is an end face of a downstream side of the upstream side member (23; 38, 39; 43, 44), wherein the downstream side member (43,44;38,39) includes a guide face (43c,44c;38c,39c) facing the passage and having a concave shape surface arranged in the passage side as the guide face (43c,44c;38c,39c) goes toward the upstream side, wherein, when viewed in a cross section in which the upstream side member (23;38,39;43,44) and the downstream side member (43,44;38,39) are cut along a rotor shaft (Ar), an upstream side end portion of the guide face (43c,44c;38c,39c) is formed such that a swirling current flows along the guide face (43c,44c;38c,39c) and an extension section of the guide face (43c,44c;38c,39c) without colliding with the upstream side member (23;38,39;43,44), the extension section being a line extending from an upstream most end of the guide face (43c,44c;38c,39c) toward the upstream side in a direction parallel to a surface of the upstream end portion of the guide face (43c,44c;38c,39c), and wherein the extension section does not intersect with the upstream side member (23;38,39;43,44).