To prepare the polyclonal antibody of rice Argonaute 2 (OsAGO2),the coding regions of 165~401 aa and 440~570 aa of this protein was amplified by RT-PCR in this study,followed by cloned into the prokaryotic expression vector pET-23d.Afterwards,the recombinant OsAGO2 proteins were expressed and used as antigen to immune rabbits.The expression pattern of OsAGO2 was detected by Western blot analysis using antibodies prepared.The results demonstrated that two prokaryotic expression vectors were obtained,and the 30 kD and 25 kD of recombinant proteins were expressed successfully.The antibody prepared by 440~570 aa region of OsAGO2 showed higher specificity tested by immunoblotting.Western blot analysis showed that the OsAGO2 was expressed in tissues of anther,callus and spikelets.This work would contribute to study the properties and function of OsAGO2 in rice.