Abstract: The kinetics of phase transfer catalyzed (PTC) disproportionation of elemental sulfur was studied in the range of OH~- concentrationlin the aqueous phase from 0.02 to 0.14 mol/dm~3 and temperature from 45 to 70℃. A kinetic expression, R_sa=k*[Q~+]_(aq)[OH~-]_(aq)[S]_(org)~(1/2), derived from the theory of mass transfer with rapid chemical reaction in liquid liquid system can be adopted to correlate the experimental data, and the apparent activation energy of the reaction was found to be 79kJ/mol. Kinetic evidence for PTC reaction of the system was given and a mechanism of PTC disproportionation of elemental sulfur was proposed.