Objective To observe the effect of granulocyte colony-stimulating factor carried by fibrin gel on the total number of peripheral white blood cells and neovascularization of ischemic muscle in rat hindlimb ischemia model.Methods Thirty male SD rats were subjected to right hindlimb ischemia and randomly divided into three groups:Gel + G-CSF,G-CSF,and PBS,respectively injected with Gel+G-CSF,G-CSF and PBS.WBCs was detected before and 1,3,5,7 days; At first week and fourth week after surgery,5 rats in each group were sacrificed,and after histological detections was performed,blood vessels density counted.Results The peak value of WBCs counts in group Gel + G-CSF (14.69 ± 1.11 × 109/L)appeared at postoperative day 1 was significantly lower than that in group G-CSF (21.00 ±2.26 × 109/L) at postoperative day 3.The capillary density in group Gel + G-CSF (686 ± 108/mm2) was significantly higher than that in group G-CSF (491 ± 110/mm2) and group PBS (252 ± 78/mm2),P ＜ 0.05.The α-SMA-positive blood vessel density in group Gel + G-CSF (6.1 ± 0.8/mm2) was significantly higher than that in group PBS (2.6 ± 1.3/mm2),P ＜ 0.05.In group Gel + G-CSF,there were many VEGF-positive cells infiltrating in ischemic limb.Conclusions Gel + G-CSF promotes neovascularization in ischemic muscle,and induced more modest WBCs counts increase than the treatment with G-CSF.