Streptococcus suis(SS) is an important swine pathogen. Among the 33 described serotypes, serotype 2 (SS2) is an important zoonotic agent responsible for great economic losses and public health worldwide. It can cause a diverse range of diseases, such as meningitis, septicemia, arthritis, pneumonia, endocarditis and streptococcal toxic shock-like syndrome. In the summer of 2005, a human S. suis outbreak occurred in Ziyang City, China which had lead to 38 human death. Patients showed symptoms with acute onset, high fever accompanied by headache and systemic poisoning, severe toxic shock, meningitis, etc. Until now, the precise pathogenic mechanisms were still unclear, more work was needed. As one of representative SS2 isolates in the big outbreak, the sequencing could provide knowledge for further understanding in the pathogenic mechanism of this pathogen.