Following the outbreak of COVID-19, many countries implemented a form of mandatory vaccination to increase COVID-19 vaccination rates. However, people’s attitudes toward vaccine mandates were split, and scholars pointed to their psychological foundations. This study added to this body of research and examined the relationship between psychological entitlement and attitudes toward mandatory COVID-19 vaccination. Because entitled individuals saw a vaccine mandate as a way to protect themselves from the virus, they were more likely to support mandatory COVID-19 vaccination. In September and October 2022, we surveyed 636 registered voters in South Dakota to evaluate our expectations. We measured psychological entitlement using the nine-item Psychological Entitlement Scale, social dominance orientation using the four-item Short Social Dominance Orientation scale, and partisan self-identification, COVID-19 vaccination status, education, age, and gender with single-item measures. We estimated a series of multivariate ordered logistic regression models with support for mandatory COVID-19 vaccination for all adults, support for mandatory COVID-19 vaccination for children, and support for mandatory COVID-19 vaccination for healthcare workers as the respective dependent variables. The other variables mentioned above were independent variables in all models. Results showed a positive and statistically significant association between psychological entitlement and support for mandatory COVID-19 vaccination for all adults (β = 0.029, p = 0.004), children (β = 0.041, p < 0.001), and healthcare workers (β = 0.028, p = 0.007). The correlations between social dominance orientation, partisan self-identification, and attitudes toward COVID-19 vaccine mandates were also statistically significant. The results of our study underscored the role of individual-level characteristics in shaping attitudes toward the management of COVID-19 outbreak.