Abstract: Studies on elemental fractionation and homogeneity of CGSG reference materials (CGSG-1, CGSG-2, CGSG-4 and CGSG-5) promote quality assessment and application. The elemental fractionation and within-unit homogeneity of CGSG reference materials were evaluated using Electron Microprobe and Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS). Meanwhile, the major and trace element contents were also reported. The results showed that the elemental fractionation of CGSG reference materials was negligible for 50 μm spot size. Electron Microprobe homogeneity index illustrated that the homogeneity of major elements in CGSG reference materials is approvingly acceptable, and most trace elements possess same homogeneity grade with MPI-DING reference materials. Analytical results of major elements by Electron Microprobe and LA-ICP-MS are consistent with published data within 2% and 5% errors, respectively. Analytical results of trace elements by LA-ICP-MS are generally in agreement with the published data. Some elements such as Cr, Ge, Cd, As and Tl show a larger deviation due to the large uncertainties of the analytical technique. In general, the analysis data reported here could supplement the CGSG value database.