Sorcin or soluble resistance-related calcium-binding protein, is a 22KD calcium binding protein initially identified in many multidrug resistant (MDR) cell lines. These work aimed to study sorcin gene expression in acute myeloblastic leukemia (AML), and to correlate its expression with treatment outcome of the patients.The sorcin gene expression was studied in twenty newly diagnosed AML patients, ten relapsed AML patients and ten age and sex matched normal control volunteers.Sorcin gene expression was significantly higher in AML patients than in normal control volunteers, and higher in relapsed AML patients than in those of newly diagnosed AML patients.Sorcin gene expression was significantly higher in M5 than in the other FAB subtypes, and is associated with bad treatment outcome in AML patients.