Although vaccine behaviors differ greatly by gender and age, few studies have examined vaccination at the intersection of gender and age within the Black community. We examined COVID-19 vaccination by gender and age using a survey of over 500 Black adults in Chicago, Illinois, fielded from September 2021 to March 2022. Although 54% had received at least one COVID-19 vaccine, the proportion vaccinated was considerably lower for Black men (28%) and women (37%) under 40 years old than Black men (92%) and women (86%) over 40 years (p < 0.001). Concern about vaccine side effects was the most reported barrier for unvaccinated women (56%) and men (38%) under 40 years. Our results suggest that targeted efforts to improve COVID-19 vaccine uptake in the Black community in Chicago after the initial rollout should have focused on young adults, particularly young Black men, with emphasis on addressing concern about vaccine side effects.