The invention provides a usage of a Antrodia cinnamomea powder for preparation of a composition for dispelling the effects of alcohol, which means that by administering an effective amount of the Antrodia cinnamomea powder disclosed in the invention to an subject, is capable of accelerating metabolism of alcohol and/or acetaldehyde in the subject's body, reducing a content of alcohol and/or acetaldehyde in blood, and shortening the time of the subject generating intoxicated reaction in order to achieve an efficacy of dispelling the effects of alcohol.