Abstract: Terpinolene was synthesized from pinene by the catalysis of p-tolueresulfonic acid.The final content of terpinolene in product could be maintained 38.8% and the yield of terpinolene was 39.9%. Under the condition of90 ℃,7 h,12.7% catalyst, 36% water,1.3% emulsifier.The synthesis technigue and yield of product are all superior than those at home and abroad.

Key words: pinene, toluene-p-sulfonic acid, terpinolene