PURPOSE Although data from 1975 to 1997 revealed a gap in cancer survival improvement in adolescents and young adults (AYAs; 15-39 years) compared with children and older adults, more recent studies have reported improvements in AYA cancer survival overall. The current analysis provides an update of 5-year relative survival and cancer survival trends among AYAs compared with children and older adults. METHODS We obtained data from the National Cancer Institute Surveillance, Epidemiology, and End Results Program for 17 regions to obtain recent (2010-2018) 5-year relative survival estimates by cancer type, stage, sex, and race/ethnicity by age group. In addition, we calculated 5-year relative survival trends during 2000-2014. RESULTS Across 33 common AYA cancers, AYAs and children had high 5-year relative survival (86%) and experienced similar survival improvements over time (average absolute change: AYAs, 0.33%; children 0.36%). Among AYAs, 73% of cancers had improvement in 5-year relative survival since 2000. Despite this overall progress, we identified cancers where survival was worse in AYAs than younger or older patients and cancers that have had either a lack of improvement (osteosarcoma and male breast) or decreases in survival (cervical and female bladder) over time. Furthermore, males had inferior survival to females for all cancers, except Kaposi sarcoma and bladder cancer, and non-Hispanic Black/African American AYAs experienced worse survival than other racial/ethnic groups for many cancers considered in this study. CONCLUSION Future studies should focus on identifying factors affecting survival disparities by age, sex, and race/ethnicity. Differences in biology, clinical trial enrollment, delivery of treatment according to clinical guidelines, and supportive and long-term survivorship care may account for the survival disparities we observed and warrant further investigation.