Abstract: In present study, a PCR method was established based on the ORF2 gene of PCV-2 published in GenBank to detect the PCV-2 in clinical samples from three pig farms. The results showed that a specific band with the anticipated size of 630 bp was obtained. A total of 30 clinical samples from three pig farms were detected for the presence of PCV-2 by the established PCR method and 9 of them were PCV-2 positive, the positive rate was 30%. It was indicated that the PCR method established in this study was a fast, sentitive and efficient strategy for the molecular diagnosis of PCV-2 infection in porcine farms.