It is provided a process for producing a purified essential oil excellent in safety and quality with high productivity from an essential oil comprising a harmful contaminant such as an agricultural chemical by simply and smoothly removing the contaminant with high removal rate without causing poor balance of flavor which the essential oil originally has, decrease of flavor strength and the like. It relates to a process for producing a purified essential oil by treating an essential oil comprising a contaminant with an active carbon to remove the contaminant and the removal rate of the contaminant is further improved by using an active carbon activated with a chemical, particularly an active carbon activated with zinc chloride, in the treatment, or by conducting the treatment at a low temperature of room temperature or lower, particularly at −25° C. to 5° C.