Abstract： [Purpose]To analyze the incidence and mortality of cancer in 2019 and trends from 2015 to 2019 in cancer registration areas of Inner Mongolia Autonomous Region.[Methods]The pooled database of 30 cancer registries in Inner Mongolia in 2019 were used.The crude incidence/mortality rates,age-standardized rates by Chinese standard population(ASIRC/ASMRC),cumulative rates and the rank of cancers were calculated and stratified by sex,area and age group,respec-tively.Trends of cancer incidence and mortality from 2015 to 2019 were estimated by Joinpoint regression model.[Results]In 2019,the crude incidence in cancer registration areas of Inner Mongolia Autonomous Region was 272.18/105,ASIRC was 179.00/105;and the incidence rate of males was 13.81％higher than that of females,the incidence rate in rural areas was 5.61％higher than that in urban areas.The top five cancers with high incidence were lung,female breast,colorectal,liver and stomach cancer.The crude mortality was 156.64/105,ASMRC was 101.26/105,with the mortality rate of males being 74.17％higher than that of females,and the mortality rate in rural areas being 1.53％higher than that in urban areas.The top five cancers with high mortality were lung,liver,stomach,esophageal and colorectal cancer.From 2015 to 2019,ASMRC in Inner Mongolia showed a significant downward trend(AAPC=-2.74％,P=0.045).[Conclusion]Lung,liver and digestive tract cancers in the middle-aged and elderly populations remain the focus of cancer prevention and control in Inner Mongolia,while the rising trends of colorectal,breast and thyroid cancers should be closely monitored.