Purpose: The two main subtypes of primary liver cancer are hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA). We aimed to produce worldwide and regional estimates of the distribution of these subtypes based on high quality data. Methods: Population-based cancer registry data were used to compute sex-specific proportions of HCC, iCCA, and other specified histology. The proportions were applied to sex- and age-specific liver cancer estimates from GLOBOCAN 2018 and age-standardized incidence rates were calculated. Results: Of an estimated 826,000 cases of liver cancer in 2018, 661,000 (80.0%) were HCC, 123,000 (14.9%) were iCCA and 42,000 (5.1%) were other specified histology. In nearly all world regions, HCC was more common than iCCA, except in women in Northern Europe where iCCA was more common than HCC. The highest rates of HCC were found in Eastern Asia (14.8 cases per 100,000 person-years), Northern Africa (13.2) and South-Eastern Asia (9.5). The highest rates of iCCA were in South-Eastern Asia (2.9), Eastern Asia (2.0), Northern Europe, the Caribbean and Central America, and Oceania (all 1.8). HCC was more often diagnosed in males (M:F rate ratio ranged from 1.6 to 5.0), while the sex difference in iCCA rates was much smaller (M:F between 0.7 and 1.7). Conclusion: Uncovering the distinct patterns of HCC and iCCA by sex, country and world region is critical to further develop public health policy to reduce liver cancer burden and monitor progress in controlling the disease globally. Improved completeness of liver cancer histology registration would provide more reliable estimates for policymakers to base decisions on. Citation Format: Harriet Rumgay, Jacques Ferlay, Catherine de Martel, Damien Georges, Amal Samy Ibrahim, Rongshou Zheng, Wenqiang Wei, Valery Lemmens, Isabelle Soerjomataram. Global Incidence of Hepatocellular Carcinoma and Intrahepatic Cholangiocarcinoma in 2018 [abstract]. In: Proceedings of the 9th Annual Symposium on Global Cancer Research; Global Cancer Research and Control: Looking Back and Charting a Path Forward; 2021 Mar 10-11. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2021;30(7 Suppl):Abstract nr 44.