BackgroundVaccine hesitancy is a significant global problem resulting from the interaction of multiple factors, including mental health factors. However, the association of COVID-19 vaccine hesitancy with mental health has not been well-examined, especially in Arab culture. This study aims to identify the correlation between anxiety/fear of COVID-19 and vaccine hesitancy among Saudi adults.MethodsAn online-based survey was administered to 558 participants from all regions of Saudi Arabia using the snowball technique. However, this sample may not be representative of the Saudi adult population. Participants responded to the Questionnaire of Vaccine Hesitancy, the COVID-19-Anxiety Questionnaire (C-19-A), and the Fear of COVID-19 Scale (FCV-19S). Data were analyzed on vaccine uptake, vaccine hesitancy, coronavirus infection, and demographic variables. The predictive factors of vaccine hesitancy were examined in one model using multiple regression analysis by the Enter method (P= 0.05).ResultsCOVID-19 anxiety and fear have significant correlations with vaccine hesitancy (Phi=0.33, P=0.017; Phi=0.29, P=0.013, respectively). Anxiety and fear were higher among unhesitating participants (t =2.469, P=0.014; t=2.025, P=0.043, respectively). Participants who had previously been infected with coronavirus were more likely to be hesitant (X2 = 23.126, P=0.000). Participants who scored high in anxiety were more likely to be vaccinated (F=3.979, P=0.019) and have a secondary school or college education (F=4.903 P=0.002). COVID-19 anxiety, gender, and coronavirus infection significantly predicted vaccine hesitancy.ConclusionAnxiety and fear of COVID-19 are among the most important factors correlated with vaccine hesitancy; unhesitant people are more likely to have anxiety and fear. COVID-19 anxiety significantly predicted vaccine hesitancy. We recommend integrating psychological care into vaccination plans to help increase the uptake rate during potential subsequent pandemics. Relevant intervention programs can be designed to help increase vaccine acceptance, deal with vaccine hesitancy, and relieve psychological symptoms during major pandemics. Psychologists can provide awareness messages, counselling seminars, online mentoring, or telemental health outreach.