A nozzle device for jetting water as hot as one can enjoy bathing in it, which is supplied under pressure from a hot water supply source, into hot water in the bathtub comprising a nozzle body provided with a nozzle opening formed at the front end of the nozzle body and through which the hot water is jetted and an inner hole through which the hot water is introduced from the hot water supply source to the nozzle opening, a means for jetting not water passed through the nozzle opening, having a hole arranged coaxially with the nozzle opening and a passage through which air outside is introduced into the hot water passed through the nozzle opening, and a means for adjusting the amount of the air introduced through the air passage into the hole, said means being movable toward said nozzle opening while rotating around its axis.