The invention provides a gas-turbine fuel nozzle (1) that includes a plurality of fuel supply channels (3a) to which fuel is supplied, a plurality of fuel/scavenging-fluid supply channels (3b) to which fuel or a scavenging fluid for scavenging the fuel is supplied, and a plurality of injection holes (7a, 7b) that are provided at downstream ends of the fuel supply channels (3a) or the fuel/scavenging-fluid supply channels (3b) and that inject the fuel guided from the fuel supply channels (3a) or the fuel/scavenging-fluid supply channels (3b); a scavenging-fluid supply channel (21) that is connected to the fuel/scavenging-fluid supply channels (3b) to guide the scavenging fluid; and scavenging-fluid cooling means (23) for cooling the scavenging fluid to a temperature lower than a self-ignition temperature of the fuel.