The invention discloses a method for preparing
silicon-based oxynitride fluorescent
powder, which comprises the following steps of: weighing corresponding raw materials and silica
powder based on stoichiometric proportion of each element in the
chemical formula of the
silicon-based oxynitride fluorescent
powder, after uniformly mixing the raw materials and the silica powder, raising the temperature to 800 to 1,000 DEG C under any one of the conditions of condition a to condition c, performing reduction reaction under the condition c or the condition d, and cooling the
reaction product to roomtemperature to obtain the
silicon-based oxynitride fluorescent powder, wherein the condition a is vacuum; the condition b is the
atmosphere of
inert gases; the condition c is the
atmosphere of
nitrogen-containing gases; and the condition d is the
atmosphere of reductive gas. The silicon-based oxynitride fluorescent powder doped with various luminescent ions and prepared by the method has bright
fluorescence under the excitation of
ultraviolet ray,
near ultraviolet or visible light. The method has the advantages of low preparation temperature of the product, high
phase purity of the product, controllable particle size of the product, good
luminous intensity of the product, low cost, simple process and the like, and is easy to enlarge industrialization.