Abstract Objectives: The COVID-19 pandemic continues to claim victims around the world, and Iran is no exception from this ravage. Vaccine development led to growing optimism regarding control of COVID-19. Vaccine acceptance by the majority of the population is important for the success in controlling COVID-19. This study assessed the attitude of Iranian population toward COVID-19 vaccination. Also, the adverse effects of the COVID-19 vaccines on vaccinated individuals were reported. Method: This cross-sectional study was conducted from May to July 2021 among Iranian population. The data was collected using the online researcher-made questionnaire. The questionnaire contained 16 questions in 3 sections. Results: The questionnaire was filled out by 916 people in total. The majority of participants had 40-65 years old (N:480, 52.4%). More than half of participants were from health care team (N:543, 59.3%). The majority of participants trusted the vaccine and said they would inject it (N:582, 63.5%). However more than 80% of participants preferred non-domestic vaccines over Iranian ones. Potential adverse effect following vaccination was the main concern of responders (N:576, 62.9%). The most common adverse effects reported by vaccine recipients were temporary fatigue and muscle pain (N:313, 71.95%). The level of education, academic area and area of practice in the health system were significantly associated with the positive response to COVID-19 vaccination (P-value 0.0001, 0.0001 and 0.004 respectively). Conclusion: According to the results of this study, Iranian health authorities should provide clear information about the safety and efficacy of COVID-19 vaccines, especially domestic types, to increase public confidence and awareness regarding vaccines.