Abstract: α-Terpineol was synthesized in one-step with α-pinene and β-pinene from turpentine oil as primary materials, using H-mordenite molecular sieve（H-M） as catalyst in the presence of quaternary ammonium salt（QX）,to carry out simultaneously the reactions of ring-opening, rearrangement and hydration. Factors affecting product yield were investigated by L₁₆（4⁵） orthogonal experiment, to obtain optimum technological condition as follows: reaction temperature 80℃, QX mass fraction 8%, m_H-M:m_pinene value 0.6, m_ethylacetate:m_pinene value 0.9, m_H2O: m_pinene value 1.4. α-Terpineol yield was 43.5% under this technological condition.The products were measured by GC-MS, and 15 components were identified. Main components are pinene, limonene, eucalyptol, 1-methyl- 4-（1-methylethyl）-1,4-cyclohexadiene, borneol and（+）-α-terpineol. An optically active α-terpineol was obtained with optical rotation +61°. The product with right pure odor is useful as a fragrance.

Key words: terpineol, H-mordenite molecular sieve, quaternary ammonium salt