Research has shown that student access and achievement in advanced precollege chemistry has been largely inequitable when considering certain demographic factors. In this nonexperimental observational study, an intersectional analysis of ethnicity and gender was utilized to examine United States student participation and performance (N = 146,610) in Advanced Placement (AP) Chemistry during the 2019 examination administration. The theoretical framework was based upon the "intersectional hypothesis," which suggests that intersectional groups may have unique roles in social hierarchies; exploring disparities in the performance of these groups may inform policies and practices in advanced chemistry study in precollege settings. Methods included chi square goodness of fit and analysis of variance with post hoc Games-Howell tests. Results indicated that access to AP Chemistry was statistically equitable across gender, but large disparities existed among ethnic and intersectional groups (ethnicity x gender) in terms of access. Ethnic groups traditionally underrepresented in STEM were underrepresented in AP Chemistry participation. Intersectional groups showed differences in performance with a medium to large effect size. Women of color had the highest failure rates, followed by men of color, suggesting that widescale interventions are necessary to improve preparation for advanced chemistry, acquisition of chemistry knowledge and skills, and a reduction in the achievement gap in AP Chemistry performance. Implications for policy and practice are discussed.