The fraction distributions,availabilities,and mobility of Hg,Ni,Cd,Cr,Zn,As,Cu,and Pb in municipal sludge of Nanchang City were investigated.Results showed that the extraction percentages of Pb and Cr by Tessier's sequential extraction procedures were 96.5%～94.6% and 90.1%～90.3%,respectively.The sums of each fraction of heavy metals were in agreement with the total contents of heavy metals,which means that the fraction distributions of heavy metals in the municipal sludge given by Tessier's method were reasonable.There were significant differences in fraction distributions of heavy metals in the two kinds of municipal sludge(QCSS and ZCSS)and among the different fractions of the heavy metals.By the availabilities of heavy metals,the heavy metals in QCSS were in the order of HgNiAsCdCuCrZnPb and by the mobility of heavy metals,HgNiCdCrZnAsCuPb,respectively.In ZCSS,the corresponding orders were CrHgCuCdNiZnAsPb and CrHgCdNiZnCuAs≈Pb,respectively.The result may provide a scientific basis for the harmful assessment of heavy metals in the agricultural utilization of sewage sludge.