The invention provides a method for simply, rapidly and accurately measuring the content of silicon dioxide in optical glass. The method comprises the following steps: (1) putting a glass powder sample into a container, and adding a mixed fusing agent composed of borax and anhydrous sodium carbonate; (2) heating and fusing a mixture to be transparent, and cooling; (3) adding hydrochloric acid to dissolve until the solution is acidic; diluting by using water to obtain a sample solution; (4) preparing a standard series solution of silicon; (5) determining the standard series solution by a plasma atomic emitted spectrometer; determining a sample solution and automatically calculating the content of silicon element in the sample solution by an instrument; and (6) calculating the content of the silicon dioxide according to a formula. According to the method, an ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry) method is used for measuring the SiO2 in the glass and is simple and rapid; an analysis procedure is reduced, the analysis efficiency is improved and manual analytical errors are reduced; the repeatability and the accuracy of measurement can be obviously improved; the interferences on a test by aluminum and titanium can be effectively avoided; meanwhile, the low-content silicon can be measured simultaneously and the method is rapid and accurate.