Objective To study the role of insulin-like growth factor 2 (IGF- Ⅱ ) in the proliferation and degeneration of hemangiomas. Methods The expression of IGF- Ⅱ and Ki-67 was detected with SP im-munohistochemical method in 52 specimens of hemangiomas, 27 of vascular malformation and 5 of normal skin. The expression of IGF-Ⅱ mRNA was examined by reverse transcription polymerase chain reaction (RT-PCR) in specimens from 9 cases of hemangiomas and 5 of vascular malformation. Results The labelling indexes (LI) of IGF- Ⅱ and Ki-67 and the expression of IGF- Ⅱ mRNA were significantly higher in heman gioma than those in vascular malformation and normal skin (P