Chemical analysis of major elements has been carried out by XRF method, using fused glass disks prepared with 1:10 proportion of sample: flux. Standard samples of the Geological Survey of Japan were employed to draw the calibration curves for the following oxides: SiO_2, TiO_2, Al_2O_3, Fe_2O_3, MnO, CaO, MgO, P_2O_5 and K_2O. On the basis of these curves, total analysis was performed on 6 unknown samples of granite. Contents of Na_2O were determined separately by flame photometry and the results were discussed with special emphasis to silica determination.