Provided is a nozzle or a stopper having a gas blowing function, which is capable of preventing irregular breaking to be triggered by a gas outlet or a gas passage path communicated with the gas outlet, or, even in the event of breaking, preventing expansion of the breaking, and a combination of the nozzle and the stopper. The nozzle comprises: a fitting engagement region refractory material layer composed of a fitting engagement region refractory material; a nozzle body composed of a different refractory material from the fitting engagement region refractory material (main body refractory material); and a gas outlet provided in at least one boundary area between the fitting engagement region refractory material layer and the main body refractory material in a surface of the nozzle contactable with molten steel.