Objective To explore a practical method using hypoxic preconditioning agent to increase neovascularization of the prefabricated flap,so as to increase its survival rate and application safety.Methods An abdominal prefabricated flap model was created in rats via a 2-stage operation.The rats were allocated into 4 groups according to different treatment.Group 1:control group;Group 2 and 3 received desferrioxamine(DFO)treatments after the first stage operation by intraperitoneal and subcutaneous injection respectively.Group 4 received a delay procedure 1 week before the second stage operation.Flap survival rates and capillary densities were evaluated in the 4 groups.The influence of DFO and Dimethyloxallyl Glycine(DMOG)on the dermal fibroblasts was also studied in vitro.Results DFO treatment as well as surgical delay greatly increased flap survival rate and capillary density compared to the blank control.In vitro,DFO and DMOG treatment up-regulated the expression levels of several angiogenic factors in the dermal fibroblasts.Conclusion The application of DFO after the first stage operation of flap prefabrication can greatly promote the neovascularization of prefabricated flaps.