Abstract: The purpose of this study was to investigate the effect of sodium hypochlorite(NaClO)on preventing the Salmonella cross-contamination in broiler chilling process. Three batches of chicken samples were washed consecutively at different NaClO concentration(0~70 mg/L)and initial pre-chill prevalence(25%~100%). The post-chill prevalence of each batch and total chicken samples were determined respectively. The results showed that the post-chill prevalence of Salmonella on total chicken samples were 88.9%,38.9%,36.1% and 36.1% when the NaClO concentration in chilling water were 0,20,50 and 70 mg/L,respectively,indicating that the chlorinated water could reduce the Salmonella cross-contamination effectively(p<0.05). When the NaClO concentration was 50 mg/L,no Salmonella survivor in chilling water was detected,which could prevent the cross-contamination. Color analysis showed that there was no significant adverse effect on sample color with the treatments of 20~70 mg/L NaClO washing(p>0.05). This study could provide useful information for preventing Salmonella cross-contamination in broiler chilling process at slaughter house,and quantitative microbial risk assessment as well.