In developing countries, HIV, sexually transmitted infections (STIs) and unintended pregnancy take an enormous toll on women's reproductive health, yet preventive programmes are lacking as married women's risks are frequently underestimated. We examined predictors of married Bangladeshi women's attitudes towards safer-sex negotiation using data on 15,178 currently married women aged 15–49 from the 2011 Bangladesh Demographic Health Survey. Approximately 92% of women believed that a wife's refusal to have sex with her husband is justified if he has an STI. Multilevel logistic regression analysis revealed that the likelihood of a woman holding this belief increased with her autonomy, as measured by the ability to go to a health centre/hospital without another adult, participation in household decision making and rejection of wife beating (p < 0.001). Other significant predictors were knowledge/awareness of STIs (p < 0.05), living in Dhaka division (p < 0.001) and younger age (p < 0.01). Our findings suggest that sexual health education programmes may be more effective if they include strategies to address social norms and cultural practices that limit women's autonomy in society.