The compounds containing structural Fe(Ⅱ) including sulphate Green Rust(GRSO4) and carbonate Green Rust(GRCO3) used in this study were synthesized in laboratory.The reducing capacity of GR for o-chloronitrobenzene(CNB) as well as the reaction pathway and products was investigated.Results show that reductive transformation of o-chloronitrobenzene by GRSO4 and GRCO3 is effective and the reducing capacity of GRSO4 is more than GRCO3,the structural Fe(Ⅱ) as the main active material.O-chloronitrobenzene is mainly transformed to o-chloroaniline after reaction,GR becomes the magnetite and goethite by oxidation reaction.pH is the important influence factor on the reducing capacity of GR and the rise of pH value can increase the reduction rate of CNB by GR.