Objective To explore the best way and the security of hypertrophic scar treatment by surgery combined with isotopic 90 Sr-90 Y or triamcinolone acetonide.Methods Hypertrophic scar of rabbit ears were divided into direct treatment group (Group A received 90 Sr-90Y irradiation,Group D received triamcinolone acetonide),two days 90 Sr-90 Y irradiation after surgery repair group (Group B),one week treatment after surgery repair group (Group C received 90Sr-90 Y irradiation,Group E received triamcinolone acetonide),saline injection group (Group F received saline directly,Group G received saline injection after surgical repair one week later),Group H received nothing,and then the histological changes were compared in each group.Results The 90Sr-90 Y exposure groups (Groups A,B,C) and triamcinolone acetonide injection groups (Groups D and E),the number of fibroblasts,collagen fiber surface density,microvessel counts and α-SMA-positive particle optical density values were significantly lower than the saline groups (Groups F,G) and blank control group.The most obvious group was Group B; Groups A,C,D,and E were not statistically significant.The number of melanoma cells of 90Sr-90Y exposure group (Groups A,B,and C) was significantly lower than other groups,with statistically significant difference.Atypical cells were not found in 90Sr-90 Y applicator exposure group.Conclusions Isotope 90 Sr-90 Y and triamcinolone acetonide inhibits the proliferation of the rabbit ear hypertrophic scar,the scar tissue fibrosis is reduced significantly,but there is no significant difference between the two effects.Early isotope 90 Sr-90 Y intervention on hypertrophic scar can achieve better results.Hypertrophic scar by isotope 90 Sr-90 Y radiation is easy to cause depigmentation,but generally does not cause cancer. Key words: Hypertrophic scar; Strontium radioisotopes; Ytterbium; Triamcinolone acetonide