Introduction: In the worldwide COVID-19 pandemic, healthcare workers (HCWs) caring for people with intellectual disabilities (ID) face a unique risk above the already heightened occupational risk all HCWs are exposed to, but literature on this specific group is lacking. Understanding why individuals are hesitant to be vaccinated for COVID-19 is essential in order to provide the right measures in improving vaccination numbers. This article reviews the influencing factors of COVID-19 vaccine willingness and hesitancy in HCWs who work with people with ID. Methods: CINAHL, APA PsycArticles, APA PsycInfo, Web of Science, Semantic Scolar, Prospero, Outbreak Science, Cochrane and Scopus were searched for papers including the attitudes on COVID-vaccination of HCWs in the field of ID-care. Only two papers were found on HCWs working with people with ID, therefore the search was broadened to HCWs in general. Twenty-six papers were identified containing quantitative and qualitative data on 43,199 HCWs spread over 16 countries worldwide. Socio-demographical predictors of vaccine willingness were extracted and analysed, as well as attitudes of vaccine willingness and hesitancy. Results: Medical doctors, people of older age, men, and those previously vaccinated with the influenza vaccine were most willing to take the COVID-vaccine. Health factors and ethics were drivers of vaccine willingness; characterised by perceived COVID-threat and wanting to protect family members and others. Distrust and lack of information were the most common drivers of vaccine hesitancy; characterised by concerns on side effects, vaccine safety, vaccine efficacy, and speed of vaccine development. Limiting to the two papers investigating HCWs in the care of people with ID, some similarities were found: (1) only older age was a predictor for vaccine willingness and (2) concerns about possible side effects and the fast development of the vaccine were the main drivers for vaccine hesitancy. Additionally, vaccine willingness and hesitancy in HCWs are not stable over time and are affected by information sources and contextual factors. Conclusions: To achieve the highest COVID-vaccination degree worldwide amongst HCWs, recommendations are made for interventions on distrust-topics to nursing staff, people of younger age, women, and those not previously vaccinated within the HCW-population. Implications: Additional research is needed to specify more precisely the attitudes of HCWs caring for people with ID in general and in more countries worldwide. [ABSTRACT FROM AUTHOR]