The purpose of this study is to research the effect of hydrogen rich water on 40`s∼60`s women`s neck skin. In general, skin aging is classified into two factors; intrinsic skin aging (a genetic factor) as well as extrinsic skin aging caused by stress, ultraviolet and external stimulus. This means that skin aging is an uncontrollable phenomenon for human beings and the recuperative powers to revive skin cell can be weakened as time goes by. In this research, however, we try to analyze whether hydrogen rich water can practically affects preventing middle-aged women`s neck skin aging or not. To do efficient research, participants in this experiment were classified into the hydrogen rich water intake group (Exp.) and the control group (Cont). Participants in the eight women respectively. The hydrogen rich water taking 1.5L-2L every day, was provided for (Exp.) group from April 2016, for 12 weeks until June 2016. The average variations of neck skin melanin figures showed that experiment group decreased by 7.4%, but control group increased by 7.3%, respectively, 14.7% less neck skin melanin figures in experiment group than control group. The average variations of neck skin erythema figures showed that experiment group decreased by 5.3%, but control group increased by 5.3%, difference in a 10.6%. The results of the experiment is that hydrogen rich water intake has a positive effect on neck skin aging and this leads a valid conclusion that some hydrogen radical has an anti-skin aging effect, which is characterize by melanin, erythema, sebum, pH and moisture.