The present invention provides a fuel valve (50) for ejecting gas fuel into a combustion chamber of a compression ignition type internal combustion engine. The fuel valve includes: a thin and long fuel valve housing (22) having the rear end and the front end; a nozzle (54), wherein, the nozzle has a thin and long nozzle body, the nozzle body has the hollow interior connected to a chamber (55) of a nozzle hole (56), and the nozzle (54) is arranged on the front end of the fuel valve housing (52); a gas fuel inlet port (53), which is connected to a high pressure gas fuel source (60) in the thin and long fuel valve housing (52); ignition liquid inlet ports (78,79), which are connected to an ignition liquid source (57); a device for establishing timing fluid connection between the gas fuel inlet port and an ignition space (55); and a device, which is configured to transmit defined ignition liquid to the chamer (55) on time so as to ignite gas fuel inside the chamber (55).