Abstract: Composition of the surface sediments with particle sizes of 0-10cm were analyzed at three representative sites (Caohai, mid-lake, southern Waihai) from Dianchi Lake. Physiochemical properties and the concentrations of Cu, Cr, Ni, Zn, Pb, Fe, Mn and Cd in different particle-size fractions of the sediment were measured. The distributions in the surface sediment of different particle size were studied, as well as the normalization of metals concentrations was taken. The results showed that the surface sediments of the Dianchi Lake were dominated by the particles with sizes lower than 250μm. Silty (4-<63μm) made up of the biggest fraction among the four sizes with average of 60%. Besides, the clay (<4μm) was secondary, accounting for 19%. The overall most of heavy metal concentration increased with the particle size decreases. The average ratio of heavy metals in silts (<63μm) reached 79%, which was significantly higher than that in extremely fine sands (63-<125μm) and fine sands (125-<250μm). Cr, Cd, Cu, Pb, Zn and Ni have a peak concentration in the range of 4-<63μm with similar concentrations and enrichment properties. The six heavy metals concentrations mentioned above in <63μm fraction were 2.04,9.77,4.35,5.11,3.47and 4.60times of their local soil background values, respectively. Fe and Mn have no strong enrichment in these four particle sizes. No large difference was found between results calibrated by the clay concentration and calculated concentrations in initial sediments. Results of heavy metals in different size fractions were calibrated by the clay concentration in agreement with that of reference element calibration. In conclusion, both of these two methods were useful in calibration of heavy metals concentration in different size fractions of sediments from the Dianchi Lake.