BACKGROUND: Inequality in mortality among patients with colorectal cancer in the United States has been documented, but the trends over time and the factors contributing to racial/ethnic disparities in all-cause and cause-specific death are unknown. METHODS: This cohort study used the Surveillance, Epidemiology, and End Results (SEER) registry to analyze patients diagnosed with colorectal cancer from 1992 to 2021. We calculated the cumulative incidence of death for all racial/ethnic groups (Black, White, Hispanic, Asian or Pacific Islander [API], and American Indian or Alaska Native [AI/AN]) by diagnostic period and cause of death. We quantified absolute disparities using rate change in 5-year cumulative incidence of death and used discrete-time models to estimate relative racial/ethnic disparities and the contribution of factors to disparities in death. RESULTS: The 5-year cumulative incidence of colorectal cancer and all-cause death among Black patients decreased. AI/AN and Black patients consistently had the highest risk of death between 1992 and 2021. Between Black and White, the adjusted HR for all-cause death difference increased from 1.14 (1.10-1.17) in 1992-1996 to 1.29 (1.23-1.35) in 2017-2021. Adjustment for stage at diagnosis, first course of therapy and socioeconomic status explained 46.5 % of the Black-White disparities and 38.4 % of the AI/AN-White all-cause death disparities. CONCLUSION: Persistent racial/ethnic disparities in patients with colorectal cancer, especially in AI/AN and Black, call for new interventions to eliminate health disparities. Our study provides vital evidence to address racial/ethnic inequality.