The present invention provides a process for producing bisphenol A using a horizontal belt filter equipped with a filter cloth having a long operating life and a capability of exerting stable filtration performance. The horizontal belt filter is used for solid/liquid separation of slurry prepared by reacting phenol and acetone in the presence of an acid catalyst and then crystallizing an adduct of bisphenol A and phenol from the resulting phenol solution of bisphenol A. The filter cloth is woven out of yarns having uniform diameters and has an air permeability of 50 to 100 ml/cm 2 sec.
