Chrome ore samples were digested with Na2O2. After the whole process of high temperature melting extracted with hot water-hydrochloric acid, the SiO2 in sample solutions was directly determined by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES), adding Au as an internal standard element. The matrix interference is discussed in this paper. The results show that the recoveries of SiO2 are lower than 92.5% when the content of Na is higher than 300 mg/L. Compared with conventional chemical analysis, the measured values of SiO2 are in agreement with the certified values. However, the cumbersome procedure, time consuming, heavy workload of conventional chemical analysis methods can be overcome as the work efficiency is improved with this method. It can also be used for the simultaneous determination of Al, Fe, Ca, Mg and P in chrome ore samples.