AIM:To evaluate the change of the function of macular area after intravitreal injection of triamicinolone acetonide for treatment of trauma induced persistent macular edema. METHODS:Twenty eyes with persistent macular edema induced by trauma were injected 0.1 milliliter triamicinolone acetonide into vitreous.Their visual acuity, thickness of nerve fibers layer of macular,incubation period and response densities of N1,P1 waves of the multifocal electroretinography were studied. RESULTS:After 3months’ treatment , their average visual acuity and thickness of nerve fibers layer of macular were 0.78±0.11 and 158.00±13.73μm;before treatment they were 0.21±0.09 and 321.67±42.24μm, incubation period and response densities of the N1,P1 waves of multifocal electroretinography’ s 1 and 2 rings decreased. Compared with those before treatment, there were significant statistical difference(P<0.01). CONCLUSION:Intravitreal injection of triamcinolone acetonide is a safe and effective way to treat the persistent macular edema induced by trauma, the function of macular area improve after edema dismissing of macular area.