Based on the lab test results and information collected from 235 sows unvaccinated against PRRS virus, including 205 clinically heathy ones being not in PRRS outbreaks, and 30 sows in PRRS outbreak in the third quarter of 2010, which were raised in small householders in three districts of province, their reproductive performance was evaluated in cases of PRRSV infection or in cases of PRRSV-Leptospira coinfection by serological test. Detected PRRSV was Chinese highly pathogenic strain and only found in sows with high level of antibody against PRRSV in the outbreak. Both cases of sows (out or in PRRS outbreak) were coinfected by PRRSV and Leptospira. Reproductive performance of sows were influenced by sole PRRSV infection or by PRRSV-Leptospira coinfection.