Abstract: Production of cumene by alkylation of benzene with propylene on a solid phosphoric acid catalyst, using in a first step a plurality of catalyst beds in series and in a second step a single catalyst bed, using an overall benzene/propylene molar ratio of at least 5:1, continuously delivering the benzene to the first bed, continuously delivering a series of streams of liquid propylene respectively to the first bed and, in the form of a cold stream, between each pair of contiguous beds, and carrying out a partial recycle of reaction products of the second step as a cold stream between the first and the second step, and using a benzene/propylene molar ratio higher than 13:1 at the inlet of each bed of the first step, and higher than 25:1 at the inlet of the bed of the second step.