Objective: To analyze the trend of the burden of leukemia among people under 35 years in China from 1990 to 2019. Methods: Incidence, mortality and disability-adjusted life years (DALY) of leukemia among people under 35 years in China from 1990 to 2019 were collected by using the Global Burden of Disease (GBD) Study Database 2019. The trends in leukemia incidence, mortality and DALY rates were analyzed using the average annual percent change (AAPC) and age-period-cohort model. Results: From 1990 to 2019, the incidence, mortality and DALY rates of leukemia among people under 35 years in China showed a downward trend (AAPC=-2.336%, -3.604% and -3.589%, all P<0.05), with more pronounced downward trends in females (AAPC=-3.209%, -3.787% and -3.818%, all P<0.05) than in males (AAPC=-2.521%, -3.292% and -3.306%, all P<0.05). According to the age-period-cohort model, the risks of leukemia incidence, mortality and DALY rates decreased with increasing age. Among them, the children under 5 years had the highest risks of leukemia incidence, mortality and DALY rates (RR=4.697, 2.718 and 3.059). Over time, the risks of leukemia incidence, mortality and DALY rates also decreased from 1990-1994 (RR=1.217, 1.264 and 1.296) to 2015-2019 (RR=0.901, 0.696 and 0.691). With regard to birth cohorts, the risks of leukemia incidence, mortality and DALY rates first increased and then decreased, peaking in the 1986-1990 birth cohort (RR=1.335, 1.192 and 1.231). Conclusions The incidence, mortality and DALY rates of leukemia among people under 35 years in China from 1990 to 2019 showed a downward trend. Males and children under 5 years were the key populations for leukemia prevention and control.