Abstract: We conducted a study on allophycocyanin proteins ApcE and ApcF from Anabaena sp.,PCC7120 bound PCB in Escherichia coli and two-hybrid bacteria system of ApcE and ApcF.Results showed that the λ_max of absorption and fluorescence spectra of PCB-ApcE/PCB-ApcF were the same as the λ_max of PCB-ApcF before purification,and the same as the λ_max of PCB-ApcE after purification,indicating that ApcE and ApcF could not form a compound.While the transcription of pBT-apcF and pTRG-apcE could grow in the non-selective growth medium,they could not grow in the selective growth medium containing 3-amino-1,2,4-triazole(3-AT).The HIS3 reporter gene did not engender during the transcription,indicating there were no interactions between ApcE and ApcF.