COVID-19 is a pandemic that threatens public health worldwide. Dentists working at great risk play an essential role in protecting public health against coronavirus. This study aimed to evaluate the dental patients' attitudes and behaviors towards and knowledge and fear of COVID-19. We conducted a self-report questionnaire-based survey from 10.26.2020 to 01.12.2021 and included 1110 dental patients who applied at the Department of Dentomaxillofacial Radiology of Istanbul Medipol University Dental School. We divided the survey into four divisions: 1) Patient's knowledge about COVID-19, 2) attitudes, 3) behavior, 4) patient's fear of COVID-19. We calculated the Cronbach's alpha coefficient for the reliability of the COVID-19 Fear scale and evaluated significance at the p <0.05 level. 84.6% of the participants believed that COVID-19 could be transmitted by aerosol. 94.1% of the participants considered COVID-19 a risk for their health and 93.3% that their social life was affected. 46.3% only wanted to have emergency dental treatment and postpone their dental care, and only 7% applied to the clinic for the aesthetic process. Women had a higher fear level of COVID-19 than men. We found the knowledge, attitudes, and behaviors of the patients who applied to the dentomaxillofacial radiology positive towards COVID-19. Dental health professionals should take extra measures in dental clinics to prevent the spread of COVID-19, and more efforts should be made to improve public knowledge, attitude, and behavior.