In order to systematically explore the effects of fumed alumina on powder coatings，the effects of different specific areas and addition amounts of fumed alumina on the properties of the powder coatings were investigated. The dispersion state of alumina as well as the surface micro-morphology were observed using scanning electron microscopy（SEM）， energy-dispersive spectroscopy（EDS）and metallographic microscopy. The properties such as powder flow rate，glossiness and roughness of powder coatings were examined，and the mechanism of fumed alumina to enhance the powder coating loading rate and wear resistance was also studied. The results indicated that there existed an addition threshold of fumed alumina to affect the powder coating loading rate and mechanical properties，which was influenced by the specific surface area of fumed alumina. The specific area of fumed alumina should be greater than 70 m²/g and the different addition amount had the different effect on powder coatings. A low addition amount（0. 1%）could increase surface charges performance，a medium addition amount（0. 3%） increased fluidity and a high addition amount（0. 6%） introduced decreased electrostatic shelding effect and greater wear resistance.