Objective To observe P53 expression from invasive,proliferative and aged parts of keloid to explore the aggressive growth characteristics of keloid.Methods surgical tissues of 16 keloids and 16 normal skins were investigated by immunohistochemistry with anti-P53 antibody.The P53 expression was observed and compared among different parts of keloid and normal skin.Results The P53 expression in the invasive part of keloid was stronger than those in the proliferative and aged parts of keloid and normal skin(P0.01).The P53 expression in the proliferative part in keloid was stronger than those in the aged part of keloid and normal skin(P0.01).There was no significant difference of P53 expression between the aged part of keloid and the normal skin(P0.05).Conclusion High P53 expression may be one of possible reason accounting for the aggressive growth of keloid.