Ligusticum wallichii is a flowering plant in the carrot family best known for its use in traditional Chinese medicine where it is considered one of the 50 fundamental herbs. It is known by the common names chuānxiōng and Szechuan lovage. Ligusticum chuanxiong Hort. is native to India and Nepal. A new sesquiterpenoid named (-)-alloaromadendrane-4β,10α,13,15-tetrol was isolated from the rhizome of Ligusticumchuanxiong Hort., together with two known compounds, campest-4-en-3-one and 3-carboxyethyl-phthalide. Their structures were elucidated on the basis of spectroscopic and chemical analysis. All the compounds showed mild antimicrobial activity. Ligusticumchuanxiong oil is a kind of volatile oil from rhizome of ligusticumChuanxiong (VOC). It is pharmacologically active in treating a variety of diseases.  Biologically active compounds in the plant include tetramethylpyrazine.