Background: The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is evolving,the newly emerged Omicron variant being the dominant strain worldwide, and this has raised concerns about vaccine efficacy. The purposes of this survey were to examine the extent to which healthcare workers (HCWs) intend to receive a second booster dose of the COVID-19 vaccine and the factors that influence their willingness to accept it. Methods: The study was conducted among HCWs who were randomly selected from four public hospitals in the Campania region, Southern Italy. Results: A total of 496 HCWs answered the questionnaire (a response rate of 61.2%). Among the respondents, 20.8% indicated a score of 10, using a 10-point Likert-type scale, regarding the usefulness of a second COVID-19 vaccine booster dose. Physicians, HCWs who believed that COVID-19 was a severe disease, and those who have acquired information about the second booster dose from scientific journals were more likely to have this positive attitude. Slightly more than half of HCWs self-reported willingness to receive a second booster dose. Respondents who believe that HCWs are at higher risk of being infected by SARS-CoV-2, those who have a higher belief that COVID-19 is a severe disease, and those who have a higher belief that a second booster dose is useful were more willing to receive a second booster dose. The main reasons for those who had a positive intention were to protect their family members and patients, whereas, the main reasons for not getting vaccinated or for uncertainty were that the dose does not offer protection against the emerging variants and the fear of its side effects. HCWs of younger age, physicians, those who have a higher belief that a second booster dose is useful, and those who were willing to receive a second booster dose were more likely to recommend the booster dose to their patients. Conclusion: This study's findings highlight the necessity for designing and implementing educational interventions for improving second booster dose uptake and beliefs among HCWs and their capacity to recommend the vaccine to the patients.