Abstract: The bioavailability of heavy metals (HM) in soils and sediments could be evaluated by single chemical extraction methods. Several single extraction methods were applied to estimate the bioavailable fractions of HM in soil and sediment samples. According to the results from single extraction experiments and reports in references, the extraction performances of single extraction methods for neutral salts, weak acids, chelated reagents and combinable reagents were evaluated respectively. The factors affecting the single extraction methods for bioavailable fraction extraction were also discussed. Some suggestions on establishing and effectively unifying the single extraction methods for bioavailability evaluation of HM were put forward.