A combustion nozzle configured to discharge compressed air and fuel, to be combusted, into a combustion chamber of a combustor of a gas turbine, the combustion nozzle comprising: an air inlet configured to receive the compressed air; a nozzle orifice that opens into the combustion chamber and that is configured to discharge the compressed air; an air channel communicating between the air inlet and the nozzle orifice, wherein the air channel includes a Venturi section in which a cross-sectional area of the air channel becomes relatively small with respect to the air channel upstream and downstream of the Venturi section; a fuel channel (2φ) for receiving the fuel; a swirler that is provided on an upstream side of the Venturi section of the air channel and that is configured to change the flow of the compressed air into a swirling flow, wherein the swirler includes: a center cone disposed following a center axis along a flow direction of the compressed air of the air channel, and a vane-like member extending in a radial direction from the center cone and including a surface inclined with respect to the center axis of the air channel, wherein the compressed air flows along the surface of the vane-like member to create the swirling flow; wherein the combustion nozzle further comprises: a center-cone-interior channel including a fluid outlet, wherein the center-cone-interior channel passes through the center cone of the swirler along the center axis, and the fluid outlet opens at a distal end of the center cone on a downstream side of the flow of the compressed air, such that the compressed air is passed through the center-cone-interior channel and the compressed air is discharged from the fluid outlet toward the combustion chamber; and one or more fuel outlets, wherein the fuel channel (2φ) is configured to discharge the fuel from the fuel outlets toward a flow of the compressed air discharged from the nozzle orifice, and the fuel outlets are provided in the Venturi section. an air inlet configured to receive the compressed air; a nozzle orifice that opens into the combustion chamber and that is configured to discharge the compressed air; an air channel communicating between the air inlet and the nozzle orifice, wherein the air channel includes a Venturi section in which a cross-sectional area of the air channel becomes relatively small with respect to the air channel upstream and downstream of the Venturi section; a fuel channel (2φ) for receiving the fuel; a swirler that is provided on an upstream side of the Venturi section of the air channel and that is configured to change the flow of the compressed air into a swirling flow, wherein the swirler includes: a center cone disposed following a center axis along a flow direction of the compressed air of the air channel, and a vane-like member extending in a radial direction from the center cone and including a surface inclined with respect to the center axis of the air channel, wherein the compressed air flows along the surface of the vane-like member to create the swirling flow; a center cone disposed following a center axis along a flow direction of the compressed air of the air channel, and a vane-like member extending in a radial direction from the center cone and including a surface inclined with respect to the center axis of the air channel, wherein the compressed air flows along the surface of the vane-like member to create the swirling flow; wherein the combustion nozzle further comprises: a center-cone-interior channel including a fluid outlet, wherein the center-cone-interior channel passes through the center cone of the swirler along the center axis, and the fluid outlet opens at a distal end of the center cone on a downstream side of the flow of the compressed air, such that the compressed air is passed through the center-cone-interior channel and the compressed air is discharged from the fluid outlet toward the combustion chamber; and one or more fuel outlets, wherein the fuel channel (2φ) is configured to discharge the fuel from the fuel outlets toward a flow of the compressed air discharged from the nozzle orifice, and the fuel outlets are provided in the Venturi section. a center-cone-interior channel including a fluid outlet, wherein the center-cone-interior channel passes through the center cone of the swirler along the center axis, and the fluid outlet opens at a distal end of the center cone on a downstream side of the flow of the compressed air, such that the compressed air is passed through the center-cone-interior channel and the compressed air is discharged from the fluid outlet toward the combustion chamber; and one or more fuel outlets, wherein the fuel channel (2φ) is configured to discharge the fuel from the fuel outlets toward a flow of the compressed air discharged from the nozzle orifice, and the fuel outlets are provided in the Venturi section.