In order to study the effect of organic matter on the heavy metals leachability from municipal solid waste incineration (MSWI) bottom ash. In the project, the composted sewage sludge (CS) rich in organic matter was mixed with MSWI bottom ash in a certain proportion. e exudation test, determination of the leaching liquid pH, dissolved organic carbon and humus concentration, and the concentration of heavy metals. And the combination of CS and BA in organic compounds and metal content, calculate metal leaching rate. According to the experimental results, analysis of dissolved organic matter and humic acid concentrations and Cu and Cr leaching concentration, showed that when CS mixture ratio of 20%, organic matter and humic substances concentration and Cu and Cr leaching concentrations are highly linear correlation.