As an alternative method to the expensive and complex conventional methods for detoxification of dioxins (DXNs) and heavy metals in fly ash from municipal solid waste incineration, fly ash pellet reburning, an inexpensive and easy method to decompose DXNs and stabilize heavy metals, was investigated in terms of the heavy metal behavior during and after the reburning treatment in the incinerator. After pelletization of the fly ash, cement and water mixture with or without an additive (Na3PO4), the pellets were reburned in a laboratory-scale bubbling fluidized bed incinerator. Although the Pb landfill standard was not met without the reburning in the case of non-additive fly ash pellets, all the fly ash pellets were able to meet the landfill standards for heavy metals with the reburning. In the case of non-additive pellets, reburning at temperatures in the range of 700-900degreesC also considerably reduced the elution of heavy metals. With the reburning, Ca in the fly ash pellet was found to react with Al, Si, Mg and Cl to form mineral, which reduced the Ca solubility and accordingly reduced the pH of the leachate from fly ash pellet. Pelletizationof fly ash and a small addition of Na3PO4 to the pellet were found effective to reduce emission of heavy metals during reburning.