Cancer is a major health problem facing the entire world, and Kazakhstan is not the exception. The aim of this study was to present an epidemiological assessment of leukemia in the population of Kazakhstan during 2003-2012. This descriptive and retrospective study was based on data obtained from all oncological organizations of the whole country. Age standardized incidence rates per 100,000 population for leukemia were calculated. Totally, 6,741 new cases of leukemia were registered in Kazakhstan during the 10 year period. The mean age of patients with leukemia was 48.5. The ASRs for leukemia among men and women were 5.3 and 3.6, respectively (p<0.001). In conclusion, our results showed a high incidence rate of leukemia in Kazakhstan, especially in the north of the country. The incidence of leukemia was significantly higher in males and increased with age. Determining and controlling important risk factors of leukemia may lead to decrease in its burden.