Abstract-The TCA/ZHY catalyst (Si/Al = 3.25) was prepared by impregnation of the Zeolite HY (Si/Al = 2.89) with amount of an aquous solution of TCA. The physico-chemical properties were investigated by XRD, 29 Si and 27 Al MAS NMR, BET, SEM, NH 3 -TPD and FT-IR spectroscopy of pyridine adsorbed. The activity of catalytic of these catalysts has been carried out over the liquid-phase hydration of α-pinene to give α-terpineol as a major product and hydrocarbon as a minor products.Index Terms-TCA/ZHY, α-pinene, α terpineol, hydration.