Contamination of soil by PCB and dioxin is a serious pollution problem. The compounds have high affinity with soil, so that effective removal of the compounds from the soil is an important technical problem. The aim of this study is the development of the removal process of the contaminated compounds from soil by including the compound selectively in the cavity of cyclodextrin. In this work, to obtain fundamental knowledge for the remediation of soil by means of cyclodextrin, biphenyl was used as a model contaminated compound. We carried out fundamental studies such as enhancement of the solubility of biphenyl by cyclodextrin, the desorption of biphenyl from the soil by kneading the mixture of the contaminated soil and cyclodextrins using a twin-screw kneader, and biodegradation of the biphenyl included in an aerobic system by activated sludge. Among various cyclodextrins, hydroxypropyl-beta -cyclodextrin (HP-beta -CD) shows the highest enhancement of the solubility of biphenyl. Desorption of biphenyl from the contaminated soil is the most effective in the case of using HP-beta -CD by means of a twin-screw kneader.