The concentration of atmospheric nonmethane hydrocarbon can be measured by the method of Igari (1995). In the study, water is used. Here I describe a method for measuring the concentration of nonmethane hydrocarbons in water samples. In addition, a method for removing nonmethane hydrocarbons from water was studied. A high concentration of nonmethane hydrocarbons were observed in tap water stored in a water pipe. The concentration of nonmethane hydrocarbon in distilled water was also investigated; water obtained using a new water distillation apparatus contained high nonmethane hydrocarbon concentrations, whereas water obtained using an old water distillation apparatus had relatively low concentrations. Heating water samples for several hours in an electric kettle significantly decreased nonmethane hydrocarbon concentrations. The described method can be used to measure both atmospheric nonmethane hydrocarbon and trace nonmethane hydrocarbon concentrations in natural gases.