Vulnerability to HIV infection among wives from their injecting drug use husbands' behaviors in recent times remains an urgent public health issue. Consistent condom use could be the most preventive measure to protect them from HIY. The objective of this study is to examine factors affecting condom use among wives of Injecting Drug Users (IDUs) in ThanhHoa Province in Viet Nam, 2010. The study used data from 200 wives of IDUs and some selected variables of IDU husbands from a cross sectional study on determining HIV/syphilis prevalence and risk behaviors related to HIV transmission from IDUs to their wives in ThanhHoa Province. Snowball sampling technique was applied for sampling respondents. The results of the study reveal that HIV knowledge of wives was a main factor affecting condom use with IDU husbands. Those wives of IDUs who had good HIV knowledge were 33 times more likely to use condom consistently than those who had poor HIV knowledge. Moreover, HIV risk perception and negotiation to use condoms among wives had positive significant association with consistent condom use. In contrast, age of wives
age difference between IDUs and wives and extramarital relationship of IDUs hadnegative significant relationships on consistent condom use. The study's results suggest that Information education and communication (IEC), Voluntary counseling and testing (VCT), harm reduction program including condom distribution should be strengthened for wives of IDUs.