Background: T helper 17 (Th17) cells play a role in the pathogenesis and prognosis of acute myeloid leukemia (AML). Th17 cells produce interleukin (IL)-17A and IL-17F, that share strong surface expression and homology of the IL-23 receptor (IL-23R). Objective: To evaluate the expression of IL-17A gene polymorphism and IL-17 serum level in adult AML patients and to clarify its prognostic significance. Patients and methods: In this prospective study, 48 patients with de novo AML and 48 healthy matched controls were enrolled. Cases were diagnosed at clinical pathology and managed in Medical Oncology Departments. We evaluated both serum IL-17 levels, measured by ELISA, and IL-17A (rs2275913) gene polymorphism was assessed using realtime polymerase chain reaction (PCR) in all patients and control. All patients received “3+7” as induction, responders received 3-4 courses of high dose cytarabine as consolidation, while non-responders received salvage therapy. Results: Serum levels of IL-17 were higher in AML patients (median 27 pg/ml) vs 17 pg/ml in the control group (P < 0.001). Also, serum IL 17 level was higher in non-responders with median 37.5 (pg/ml) vs 23 (pg/ml) in responders (P < 0.001). while IL-17A mutant genotypes and alleles showed no significant relation between expression of IL-17 A gene polymorphism and response to treatment or outcome of studied AML cases. Conclusion: Serum IL-17 levels can be considered a useful diagnostic and prognostic factor in AML patients, unlike IL-17 A gene polymorphisms