The distribution and dissociation equilibria of phase-transfer catalyst, trioctylmethyl-ammonium chloride (Q(+)Cl(-)), for the system of QCI-toluene-aqueous HCrO4- solutions were measured at 298K for the systems of toluene-water or -aqueous electrolyte solutions. The evaluated distribution coefficients of trioctylmethylammonium chloride and the complex formed between trioctylmethylammonium cation and HCrO4- were correlated as a function of the ionic strength in the aqueous solutions. The dissociation constants, K-1 and K-2, were independent of ionic strength.