Segregative and recyclable solid superacids SO^2-4/TiO2 and SO^2-4/Fe2O3 were prepared by the method of coprecipitation and wet impregnation, used as catalysts in the synthesis of undecylparaben and dodecylparaben. The MIC(minimal inhibitory concentration) of the ethylparaben, propylparaben, undecylparaben and dodecylparaben against Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes, Escherichia coli, Salmonella enteritidis, Saccharomyces cerevisiae,Trichoderma spp were determined. The synthesis conditions were optimized as follows: catalyst SO^2-4/TiO2, ratio of alcohol and acid 6︰1, time 4.5 h, temperature 130～140 ℃, catalyst as 3.50% p-hydroxybenzoic acid, the yields were 55.29%, 57.02%. Second, catalyst SO^2-4/Fe2O3, ratio of alcohol and acid 5︰1, time 3.5 h, temperature 130～140 ℃, catalyst as 3.00% p-hydroxybenzoic acid, the yields were 69.14%, 72.60%. The antibacterial test showed the four parabens had antibacterial effects on them, besides the antimicrobial activities of both undecyl paraben and dodecylparabe were stronger than ethylparaben, propylparaben and their minimum inhibitory concentration(MIC) were all 0.012 5%.