In a process for producing bisphenol A by reacting phenol and acetone in the presence of hydrochloric acid as a catalyst, the improvement comprising adding the water-containing phenol separated from the reaction product mixture in the purification stage to the reaction mixture containing phenol and acetone, in such an amount that the water content in the reaction mixture is within the range of 1 to 5 wt%, said water-containing phenol being obtained from the dehydrochlorination step of the reaction product mixture, condensing the distilled off gases and liquid-separating of the condensates.