Objective The aim of the study was to develop a kind of new fluoride composite resin .We explored the practica-bility of preparing fluorinated filler by using hollow silica microsphere as a carrier of sodium fluoride (NaF) as well as its fluoride-re-lease properties in composite resin . Methods Hollow silica microspheres with mesoporous shells were prepared by the sacrificial template method.NaF was loaded into hollow silica microspheres by the impregnation method .Scanning electron microscopy ( SEM) was used to determine the morphologies of hollow silica microspheres before and after NaF loading .Hollow nanosilica microsphere con-taining NaF and NaF powder were respectively mixed with resin at the same intial NaF concentration of 13.9, 27.8 and 55.6 mg/mL for comparison, which were taken as the experiment group and the control group .The samples were put into 100 mL artificial saliva at 37℃to caculate the cumulative fluoride release quantities from 1 d to 47 d.Results The morphology of hollow microsphere did not chang significantly before and after NaF loading .In the experiment group ,the cumulative quantities of fluoride release were 0.026, 0.105, 0.21 mg/cm 2on 1 d and increased to 0.088, 0.239, 0.484 mg/cm 2on 47 d according to respective initial NaF concentration . While in the control group, the corresponding figures were 0.006, 0.025, 0.04 mg/cm2on 1 d and 0.022, 0.045, 0.056 mg/cm2on 47 d.The difference between these two groups was of great statistical significance . Conclusion Hollow silica microsphere could be used as a carrier of NaF .Fluorinated nanosilica filler using hollow microsphere promotes the fluoride release in composite resin .