Background: The use of radiation is important in different medical procedures, and to ensure a high level of good medical practice, radiation protection (RP) should be seen as a very important subject. This review shows information about the knowledge in the scope of radiation protection among healthcare professionals exposed to ionizing radiation. There are not many studies that evaluate the radiation exposure of healthcare professionals. Methods: A systematic search was performed, using PRISMA guidelines, in Pubmed and Scopus databases and manually to identify relevant articles to answer the PICOS question, "Is there an adequate level of literacy in the scope of radiation protection among healthcare professionals exposed to ionizing radiation?". This systematic review included cross-sectional studies with the following inclusion criteria: (i) in Portuguese, Spanish, or English; (ii) about literacy in the scope of radiation protection; (iii) published between 2017 and 2024; and (iv) participants must be dentists, radiographers, doctors, and nurses. The JBI critical assessment tool was used to assess the risk of bias. Results: The search identified 566 potentially relevant references, which, after applying inclusion/exclusion criteria, resulted in 12 articles. Studies found that the overall knowledge of these healthcare workers was unsatisfactory, and a lack of knowledge in radiation protection negatively affects health services' quality. Training is essential and must emphasize how radiation exposure can be minimized, safeguarding health professionals' trust and sense of security. Results showed that more years of experience make workers more attentive to protection measures, suggesting that training strategies focused on basic radiological risks and radiation safety are needed. Conclusions: Key findings recommend implementing a standardized national training program on the basic principles and safety of ionizing radiation for all healthcare professionals.