Abstract: This invention is a tail lengthener assembly and method of use to be attached to and enclose a horse's tail. The tail lengthener assembly includes 1) a tail enclosure asembly; 2) a tail hook member for attachment of the tail enclosure assembly to the horse's tail; and 3) elastic band members for attachment purposes. The tail lengthener assembly includes a plurality of tail tube member, each of an elongated tubular shape and constructed of a flexible cloth material having a main tube body with a connector member at an upper end thereof. The respective tail tube members are to receive a portion of the horse's tail therethrough and secured to an upper portion thereof. The tail hook member is operable to grasp a portion of the horse's tail and pull the same through the respective tail tube members during the method of attaching thereto. The elastic band members are of a conventional circular shape for attachment purposes.