Background Vaccine hesitancy poses a significant risk to global recovery from COVID-19. To date however, there is little research exploring the psychological factors associated with vaccine acceptability and hesitancy in Iraq. Aim To explore attitudes towards COVID-19 vaccination in Iraq. To establish the predictors of vaccine uptake and vaccine hesitancy in an Iraqi population. Methods Using a cross-sectional design, 7,778 participants completed an online questionnaire exploring their vaccination status, likelihood of infection, perceived severity infection, benefits of vaccine, barriers to vaccine, anticipated regret, subjective norms, and trust in government. Findings Vaccination rates increased with age and were greater in males, those who were married, divorced or widowed, those with children and those with underlying conditions. Vaccine hesitancy was widespread with 61.40% of unvaccinated individuals reported an unwillingness to receive a COVID-19 vaccine. In unvaccinated groups, vaccine hesitancy was associated with lower trust in the government, more negative social norms, greater perceived barriers to vaccination and reduced perceived benefits. Conclusions There is significant COVID-19 vaccine hesitancy in Iraq. Public health institutions should be aware of the influence of demographic factors, as well as personal beliefs and social norms, on individuals’ decisions to vaccinate. Public health messaging should therefore aim to be tailored to address the concerns of citizens.