Abstract Background In the United States, liver cancer is the fifth and seventh most common cause of cancer-related death among men and women, respectively. Compared with other racial or ethnic groups in the United States, Asian and Pacific Islander populations experience the highest incidence rates of liver cancer, but little is known about disparities in risk of advanced-stage disease or risk of liver cancer mortality across these heterogenous populations. Methods In a population-based cohort of 60 146 patients aged 20-79 years diagnosed with liver cancer from 2004 to 2018 identified through the Surveillance, Epidemiology, and End Results Program, we examined associations between race or ethnicity, including specific Asian and Pacific Islander subgroups, and risk of advanced-stage liver cancer and liver cancer–specific mortality. Results Compared with non-Hispanic White patients, non-Hispanic Black, Filipino, and Laotian patients had 30%-85% elevated odds of being diagnosed with stage IV liver cancer, whereas Hispanic, Vietnamese, and Chinese patients had 7%-33% lower odds of being diagnosed with stage IV liver cancer (all P <.05). Additionally, non-Hispanic Black, Kampuchean, and Laotian patients had 6%-22% elevated hazards of liver cancer–specific mortality, and Hispanic, Vietnamese, Chinese, and Korean patients had 3%-27% lower hazards of liver cancer–specific mortality (all P <.05). All statistical tests were 2-sided. Conclusions Substantial variations in risk of advanced-stage liver cancer and risk of liver cancer mortality were observed by race and ethnicity, including considerable heterogeneity across individuals broadly defined as Asians and Pacific Islanders. Further efforts to understand the contributors to these disparities are needed to inform potential targeted screening and treatment interventions.