Objective To investigate the existence and expression of porcine endogenous retrovirus(PERV)in Chinese experimental miniature pig(CEMP).Method Three pairs of specific primer(gag,pol,env)and three pairs of type-specific primer(A,B,C)were synthesized,then using the PCR and RT-PCR methods,we detected the PERV of DNA and RNA samples derived from the peripheral blood lymphocytes of CEMP.Results The results showed that the PERV existed and expressed in all samples,and the expression of PERV belonged to PERV-A and PERV-B,but the expression of PERV-C wasn't detected in all samples.Conclusion The PERV exists and can be expressed in Chinese experimental miniature pig.This research may be helpful to development of the Chinese experimental miniature pig and to assessment of the pathogen safety of PERV.