A Novel solid acid catalyst had been prepared from aromatic microporous organic polymers through a controlled sulfonation procedure. The sulfonated catalysts were characterized by FT-IR spectroscopy, X-ray diffraction, surface acidity, elemental analysis and BET method. Catalytic performance was determined via esterification of oleic acid with methanol. The results showed that the solid catalysts had high BET surface area (540 m2/g), pore volume (0.40 cm3/g) and the surface acidity was up to 2.9 mmol/g. The solid acids exhibited higher activity than amberlyst-15 for esterification of oleic acid, which conversion could reach 93% at 75℃ for 6h. The solid acid catalysts showed excellent regenerated properties.