Phosphorylation of -arbutin has been achieved using inorganic cyclo-triphosphate (P 3m ) in aqueous solution. The optimum condition for the phosphorylation of -arbutin with P 3m is -arbutin : P 3m = 0.1 mol/L : 0.5 mol/L, pH 11 and 40ºC. 4-Triphospho--arbutin was synthesized with the yield of 90%. The reaction mechanism of -arbutin with P 3m was discussed. We have successfully introduced the triphosphate group in one molecule. Phosphorylated -arbutin is expected that the permeability of -arbutin into the skin will be increased by introducing a phosphate group.