Coronavirus disease 2019 (COVID-19) has affected everyone but not equally. While many researchers examine the social inequalities of COVID-19 through income, housing, occupation, and health care accessibility, less attention has been paid to education due to lack of information for education associated with test reports. Based on the education-health gradient (Cutler & Lleras-Muney, 2006), education has causal effects on various health outcomes; even with similar income and occupation, people with higher educational attainment generally have better health outcomes. This theory has been widely adopted to research chronic and degenerative diseases, such as cardiovascular disease, diabetes, and high blood pressure. However, there is limited research on the effect of education on communicable diseases. To analyze the potential impacts of education on communicable diseases, this research examines the relationship between educational attainment and COVID-19 morbidity in 56 ZIP Code Tabulation Areas (ZCTAs) of Chicago. COVID-19 statistics were retrieved from the Chicago Department of Public Health (CDPH) and socioeconomic status (SES) statistics were retrieved from the American Community Survey 2019 (ACS-2019). Due to the variation in the test rates across Chicago, the estimates of morbidity based on infection rate tend to underestimate the true morbidity of communities with lower test rates. Therefore, this research measures COVID-19 morbidity by both test positivity rate and infection rate. Educational attainment is measured by the proportion of adults with at least a bachelor’s degree. Median income and average household size are used to control accessibility to resources and living conditions. The proportion of workers in service occupations are used to control occupational risk. Several linear regression models were conducted. Because the SES variables are highly correlated, regularization was used to combat multicollinearity. Because infectious diseases spread from one community to the neighboring communities, spatial regression was used to combat the spatial diffusion effect of COVID-19. The results show consistent negative and significant associations between educational attainment and both COVID-19 test positivity rate and infection rate. This indicates that high educational attainment lowers COVID-19 morbidity at community level. Public health experts and policymakers should make education more accessible to mitigate the social inequality in health and achieve better population health. Since this research analyzes cross-sectional data at aggregate level, the relationship between educational attainment and COVID-19 morbidity in this research might not be causal and may not be generalized to individuals. Further research utilizing individual-level and longitudinal data is required to study the causal pathways of education on infectious disease outcomes.