Background The COVID-19 has been appeared as the most remarkable global calamity of this century. Just as the COVID-19 spread throughout the world, so as the rumour and misconceptions related to it. The present study aimed to explore the prevalence of COVID-19 related misconceptions and its correlates among the older adults in Bangladesh. Methods The study followed a cross-sectional design and was conducted among 1032 participants aged 60 years and above from Bangladesh. Information was collected on 14 different locally relevant misconceptions related to the spread, prevention, and treatment of COVID-19, scored each misconception as one, and obtained a cumulative score, ranging from 0 to 14, with a higher score indicating a higher level of misconceptions. A multiple linear regression model explored the factors associated with misconceptions. Results The most common misconceptions were, all returning migrants carrying COVID-19 (45.5%), wearing personal protective equipment (PPE) in outdoors (80.1%), not going to the funeral of people died of COVID-19 (45.2%), its prevention by nutritious food (57.6%) and drinking water (39.4%), and doctor can cure COVID-19 (49.9%). Misconceptions were higher among the participants who were living alone, whose family members were not responsive to their needs during COVID-19, and who received COVID-19 related information from Radio/TV and health workers. These misconceptions were less likely among those who were aged 70-79 years, who had pre-existing non-communicable chronic conditions, who were overwhelmed by COVID-19, and who felt themselves at highest risk of COVID-19. Conclusion Overall, we found that misconceptions were prevalent among the older adults in Bangladesh. Government and other relevant stakeholders should take immediate actions to address the prevalent misconceptions through using appropriate channels, media, and message delivery systems, and applying evidence-based risk communication methods.