Fresh samples (whole plant) of Origanum vulgare L., Lamiaceae, were collected during flowering phase in August 2011, from six different production areas in China and Pakistan. More than ten specimens per collection site were collected. Voucher specimens from each site were deposited in the Traditional Chinese Medicine Ethnic Herbs Museum (TCMEHM) of Xinjiang Medical University under the name O. vulgare. The samples were identified by Yonghe Li, chief apothecary of the Chinese medicine hospital of Xinjiang. Table 1 summarizes the information about the collection sites, voucher numbers, and essential oil yields (%, referred to dry plant material), obtained by hydro-distillation in a Clevenger-type apparatus for 6 h.