History and Objectives: Because leukemia is the most common disease and one of the curable malignancies in children, the present study was performed for the determination of characteristics of children with leukemia in Kashan area.

Materials and Methods: The present study was carried out on existing data of patients undergone diagnostic procedure and treatment in the ward of pediatric disease. Demographic, clinical, laboratory, cytogenetic and immunophenotype characteristics of patients were evaluated.

Results: The study showed that frequency of leukemia in children before 1-year-old 5.5%. ALL, AML frequency were 89% and 11% respectively. The most common clinical symptoms were paleness (60.5%) hemorrhage (50%) and fever (44%). 17% of cases had WBC count more than 5000/mm³ and 27.5% of cases had platelet count less than 50000. Relapse occurred in 22% of cases with the bone marrow the most common place (11%). Frequency of leukemia was 55.5% in boys and 44.5% in girls. 50% of patients had anemia. From cytogenetic point of view 44.5% were diploid and 5.5% aneuploid and evaluation was not performed for the rest. From immunophenotype point of view cases were divided to ALL with B cell origin (50%), ALL with T cell origin (11%), ALL with unknown origin (5.5%), AML (11%) and this evaluation wasn’t performed for the 4 cases.

Conclusion: Due to nonspecific clinical signs and symptoms of leukemia among children, for early diagnosis and treatment, more percise examination by physicians is emphasized. Also more extensive studies on the prognosis of patients is suggested.