In this study, some clinical symptoms and pathological signs of post-weaning pigs infected with porcine circovirus type 2 (PCV2) were found more clearly. The typical clinic symptoms of PCV2 infected post-weaning pigs were cachexy, raw-boned, long and rough hairs, paleness. respiratory disorder, diarrhea. Gross lesions of the infected post-weaning pigs were concentrated mainly in lymphoid node superficial inguinal node was enlarged. The other gross lesions included swollen lung with brown spots, fibrin necroinflamed intestine, white spots on kidney's cortices, inflamed liver and slightly rough hepatic surface. The main histopathological lesions were decline of lymphocytes occurrence of multinucleated giant cells, infltrations of inflamed cells in many organs, interstitial pneumonia, granulomatuous enteritis, interstitial nephritis. necrosis and degeneration of liver cells The PCV2 infected pigs were surely detected by using immunohistochemistry (IHC) technique. IHC was also useful in identifying the distnbution of PCV2 antigen in the organs of infected pigs These results contributed to control the porcine circovirus disease, reduce the loss for farmers and pig industry...