A functional water containing a fluorine-containing component obtained by electrolyzing an aqueous solution containing fluoride ion using electrodes having conductive diamonds, a method of producing the same, and a method and an apparatus of rinsing electronic parts using the functional water as a rinsing water. The fluorine-containing component produced by electrolyzing the fluoride ion using the conductive diamond, has stronger rinsing effect than that of a fluorine-containing component obtained by electrolyzing the fluoride ion itself before electrolysis or the fluoride ion using other electrodes. Therefore, an amount of hydrofluoric acid used can greatly be decreased.