Incineration bottom ash of municipal waste is the last residual in waste treatment. It is necessary to decrease the residual as much as possible, besides, to recycle it in use such as construction material as one of the means. However, some environmental pollutants are contained in the ash. Therefore, it is necessary to reduce hazardous material giving a load for environment from the ash when we are going to recycle that. Then, author paid attention to a lead in particular among harmful matter and examined removal of lead by wet process in present study. Effect on leaching rate of solution concentration and L/S (ratio of liquid volume to solid mass) were examined about 11 kinds of solution to elute lead from the ash. As a result, eluents including calcium showed high leaching rate about lead. In addition, leaching rate became high with increase of L/S until L/S = 120. However, the big change was not watched in leaching rate even if L/S became more than 120. Leaching rate became high with increase of eluent concentration.