This study assessed the knowledge, attitude, and compliance to immunization guidelines among dental health-care professionals in Italy. A questionnaire was mailed to a random sample of 1000 dentists on demographic and professional characteristics; knowledge regarding infectious diseases that can be acquired/transmitted by the dentist and the vaccinations recommended; attitudes regarding the vaccinations; self-assessed information about previous vaccinations. A total of 369 dentists responded. Only 44.1 and 32.4% correctly indicated all infections that can be acquired or transmitted during their activity. Half of the dentists knew that they should be vaccinated against hepatitis B and influenza and this knowledge was significantly higher in those older, who correctly indicated that hepatitis B and influenza can be acquired and transmitted during their activity, and in those with a positive attitude towards vaccinations. Those younger, involved in specialties with low blood contact, and who did not know that hepatitis B and influenza are vaccinations recommended, were more likely to believe that is important for them to receive vaccinations. A large proportion (85.7%) reported receiving the hepatitis B vaccine, but only 56.2% the three doses. Those with a lower number of years of activity, those who knew that hepatitis B can be acquired by the dentist, those who did not need information, and those who were informed from guidelines, educational courses, and dental associations were more likely to have received the three doses or to be natural immunizated. Training and educational interventions are needed to improve knowledge and immunization coverage.