Abstract: The objective of this study was to investigate the prevalence of porcine transfusion transmitted virus (TTV) species (TTSuV1 and TTSuV2). The study was conducted in 7 different intensive pig farms of Guangdong province in China. A total of 159 swine sera were collected, and then the virus were tested using Nest-PCR. The results demonstrated that the TTSuV1 and TTSuV2 infection rates were 54.72% and 34.22% respectively, and the co-infection rate was 29.56%. We designed PCR primers based upon the conserved region of the two viruses for amplifying the two virogenes. By blast analysis with our cloned TTsuVs sequences in NCBI database, we found that our isolated TTsuV1 ORF1and TTsuV2 ORF1, have high homologousto to those known TTSuVs sequences,72%-75% and 88%-97% respectively; while have big gaps with the TTVs which infecting other species like feils, canis, tupaia, tamarin, douroucouli and homo in the nucleotide sequence. To sum up, TTSuVs had been widely distributed in Guangdong’s pig populations. This study laid the foundation for further research of the prevalence situation, serologic diagnostic methods and to prepare for safe and valid vaccine.