The noise emission behaviors of a steam microjet in subcooled water have been experimentally investigated. It is observed that the subcooled degree is an important factor to determine the noise level of a steam to water microjet. When large diameter holes are employed in a nozzle, the noise level of the microjet is insensitive to jet fluid velocity. The hole diameter of a nozzle has little effects on the maximum A weighted sound pressure,but it can move the location of the maximum noise point towards lower temperature. The noise level will decrease with decrease of the separation space of holes in a nozzle. The principle of the sound emission in a steam to water microjet is quite different from an air to air microjet. The theories and experienced formulas developed for an air to air jet noise analysis can't be simply applied to predicate the noise level of a steam to water microjet.