Objective　To assess the bioavailability of fluoride added into milk. Methods　Eight subjects were studied by testing fluoride levels in blood and urine samples collected after drinking fluoridated milk and fluoridated water respectively, according to pharmacokinitics and cross control method. Results　The bioavailability of fluoride in fluoridated milk reached 80.2% in blood analysis and 84.8% in urine analysis. The result was about 20.0% lower as compared with fluoridated water. Conclusion　Fluoride bioavailability in fluoridated milk is still high and sufficient.