A hair care product contains a yolk antibody (a yolk-derived, anti-hair antibody) which has been obtained from an egg of a domestic fowl immunized using, as an antigen, whole human hair, e.g., normal human hair or human hair damaged by permanent waving, dyeing or bleaching, hair particles obtained by grinding constituent tissues of human hair, the keratin protein extracted from the human hair, or a hydrolysate of the keratin protein.