An aircraft engine which generates thrust by discharging combustion gas rearward, comprising an afterburner, wherein the afterburner is configured to supply fuel to a gas mixture of combustion gas discharged from a core flow path of the aircraft engine and air discharged from a fan flow path of the aircraft engine for burning to increase thrust of the aircraft engine, the afterburner comprising: a rear duct provided in the outlet side of an engine case of the aircraft engine; a cylindrical liner which is provided within the rear duct and allows the gas mixture to flow, a fuel injector configured to inject the fuel in the form of liquid in the liner; an igniter which is provided downstream of the fuel injector and configured to ignite the gas mixture containing the fuel in the liner; a flame holder which is situated downstream of the fuel injector and is configured to hold flame, the flame holder including a plurality of radial flame holding members which are situated in a radial fashion inside the liner and configured to propagate flame in the radial direction; and a throttle ring which is provided at a position aligned with the radial flame holding members on the inner circumferential surface of the liner and is configured to throttle the main flow of the gas mixture, wherein between the outer circumferential surface of the liner and the inner circumferential surface of the rear duct, an annular cooling path is formed, through which, in use, a part of the air discharged from the fan flow path flows as cooling air, and the liner includes a plurality of penetrating cooling holes configured to blow out the cooling air along the inner circumferential surface of the liner, wherein the throttle ring constitutes a part of the flame holder and is an annulus flame holding member which is provided for the inner circumferential surface of the liner concentrically with the plurality of radial flame holding members and configured to propagate flame in the circumferential direction, and the inner diameter of the throttle ring constituting the annulus flame holding member decreases with distance from the upstream end thereof, and characterized in that the throttle ring is provided on the inner circumferential surface of the linear with plural supports interposed therebetween. a rear duct provided in the outlet side of an engine case of the aircraft engine; a cylindrical liner which is provided within the rear duct and allows the gas mixture to flow, a fuel injector configured to inject the fuel in the form of liquid in the liner; an igniter which is provided downstream of the fuel injector and configured to ignite the gas mixture containing the fuel in the liner; a flame holder which is situated downstream of the fuel injector and is configured to hold flame, the flame holder including a plurality of radial flame holding members which are situated in a radial fashion inside the liner and configured to propagate flame in the radial direction; and a throttle ring which is provided at a position aligned with the radial flame holding members on the inner circumferential surface of the liner and is configured to throttle the main flow of the gas mixture, wherein between the outer circumferential surface of the liner and the inner circumferential surface of the rear duct, an annular cooling path is formed, through which, in use, a part of the air discharged from the fan flow path flows as cooling air, and the liner includes a plurality of penetrating cooling holes configured to blow out the cooling air along the inner circumferential surface of the liner, wherein the throttle ring constitutes a part of the flame holder and is an annulus flame holding member which is provided for the inner circumferential surface of the liner concentrically with the plurality of radial flame holding members and configured to propagate flame in the circumferential direction, and the inner diameter of the throttle ring constituting the annulus flame holding member decreases with distance from the upstream end thereof, and characterized in that the throttle ring is provided on the inner circumferential surface of the linear with plural supports interposed therebetween.