Objective To explore the safety and efficacy of a biodegradable budesonide-loaded sponge.Methods Thirty-six adult male rats were randomly divided into compound sponge group,nasopore group and control group with twelve rats in each group.The maxillary sinus was drilled and implanted with nasopore(naspore group),com-pound sponge(compound sponge group),and the control group was not implanted with any foreign body.Collecting their heart blood and sinus mucosa after two weeks.The pathological reaction of mucosa was observed by hematox-ylin-eosin staining.Inflammatory factors were determined by enzyme-linked immunosorbent assay(ELISA).The concentrations of budesonide was calculated by reverse-phase high-performance liquid chromatography.Results Slight inflammatory cell infiltration and submucosal gland hyperplasia were found in the sinus mucosa of all three groups,the degree of inflammatory cell infiltration and submucosal gland hyperplasia in the compound sponge group were better than those in the other two groups.The expression of interleukin-5(IL-5),IL-8 and tumor necrosis factor-α(TNF-α)in the serum,sinus mucosa in compound sponge group were significantly lower than those in the other two groups(all P<0.05),and there was no significant change in cortisol concentration.The concentration of budesonide in plasma of rats in the compound group was in low level range at different detection time.Conclusions The bio-degradable budesonide-loaded sponge demonstrates its safety and efficacy,and it can be used as a biological sponge for clinical sinus post-operative tamponade,hemostasis and anti-inflammatory.