This book is compiled by the Key Open Laboratory of Urban Agriculture (North) of the Ministry of Agriculture. This paper mainly introduces the basic knowledge of plant essential oil and aromatherapy, the extraction technology of plant essential oil and base oil, the general situation of common single essential oil and base oil, and the application of plant essential oil in daily life and beauty salon. The book also briefly introduces the home cultivation techniques of vanilla and some research results of plant essential oil. The book is rich in content, novel in knowledge, practical in technology and popular in language, which has strong guidance and operability for the application of plant essential oil. It can be used by practitioners in leisure clubs such as home essential oil hygienists and beauty salons, and can also be used as a reading reference for teachers and students of related majors.