Abstract Efficient and stable solid acid catalysts, sulfonic groups functional swelling mesoporous polydivinylbenzenes (PDVB- x -SO 3 Hs), were synthesized from sulfonation of swelling mesoporous polydivinylbenzenes (PDVB- x s) by chlorosulfonic acid in CH 2 Cl 2 . Nitrogen adsorption–desorption isotherms showed that PDVB- x -SO 3 Hs have high surface area and abundant mesoporosity. Elemental analysis and acid–base titration techniques showed that PDVB- x -SO 3 Hs have high concentration of sulfonic groups. Esterifications of acetic acid with cyclohexanol, hexanoic acid with ethanol, lauric acid with ethanol and acylation of anisole with acetyl chloride showed that PDVB- x -SO 3 Hs are more active than arenesulfonic, propyl-sulfonic groups functional mesoporous silicas (SBA-15-Ar-SO 3 H, SBA-15-Pr-SO 3 H) and strongly acidic ion-exchange resin (Amberlyst 15). The superior performance of PDVB- x -SO 3 Hs is attributed to their unique features including large surface area, abundance of mesoporosity as well as high content of sulfonic groups.