Abstract: Carbon-based solid acid was synthesized from four-year old bamboo powder and 98% sulphuric acid.Oleic acid acted as raw material to simulate the high-acid value oils in the esterification reaction,using the carbon-based solid acid as catalyst to reduce the acid value of the product.Different reaction conditions and the catalyst performance were evaluated by esterification ratio of oleic acid by the single factor tests.The conversion ratio of oleic acid was 94.70% when the esterification reaction under the following conditions:reaction temperature was 120 ℃,reaction time was 4h,volume ratio of methanol to oleic acid was 1∶1 and catalyst content was 2% of the total mass of methanol and oleic acid.The conversion ratio maintained 72.47％ after repeatedly using of catalyst 5 times,which was still much higher than 62.82%,the conversion ratio of the comparation experiment without catalyst under the same reaction conditions.