Rabbits were used as experimental animals. It was investigated how much fluorine was accumulated in their bones and organs, when NaF, CaCO(3)+NaF, and AlK(SO(4))(2)+NaF were respectively administered to them. (1) Amounts of fluorine contained in organs of non administered rabbits were considered to be the physiological required amounts which was taken as food from natural source. (2) When 1 mg/kg, and 10 mg/kg of NaF were respectively administered. amounts of fluorine in bones and organs did not increase so remarkably, but when 20 mg/kg of NaF, fluorine contents increased suddenly in all bones and organs. (3) When both CaCO(3) and NaF were administered in the same amount of fluorine, fluorine was much more accumulated in bones and less in all organs than when NaF alone was administered. (4) When both AlK(SO(4))(2) and NaF were administered, it showed a reverse result as that of CaCO3 and NaF namely, fluorine was more or less accumulated in bones, but much more in organs than amounts of fluorine which was accumulated when the same amount of fluorine alone was administred.