Objective The purpose of this study was to investigate the knowledge，attitude and behaviors (KAB) of rural residents. Methods A correlative-descriptive design was used for the study. A cluster sampling of 1952 rural residents aged 18-60 years old in 8 villages of Lantian county was selected. Results The results showed as follows. The total correct rate of knowledge was 50.9%; 43.5% believed that the prevalence of HIV/AIDS in China indicated decline of the moral value; 71.3% never use condom when having sex in the past;There were positive relationships between knowledge and attitude,using condoms during sex and using condoms during first sex respectively (P<0.01). Conclusion The attitude and behavior on HIV/AIDS of the rural residents are largely determined by their knowledge.