Abstract: Objective To acquire characterisistic and the AIDS related KAP of injecting drugusers(IDUs).Methods 361 IDUs in a community of Nanchong city were surveyed by filling in the questionnaires anonymosuly.Results IDUs had some know ledge abouthIV transmission and prevention.There were a dual risks of infection of HIV by sharing needles or sex between IDUs.56.7% of the IDUs were used to shareing needles with others in the past six months.The rates of no condom using when having temporary or commercial sexual behavior were 33.3% and 52.8% respectively;the proportion of VCT (voluntary counsel and test)was only 44.6%.Conclusion Publicity and education on HIV among IDUs should still be strengthened;the importance of behavior inter vention such as providing one off clean needles,condom publicity and VCT can never be overstimated.