Objective: To study the demographic characters and diagnostic tools of acute leukemia among adults in Benghazi/ Libya. Patients and Method: A retrospective cross sectional analysis of 54 cases of AML and ALL was conducted at hematology department at Benghazi medical center (BMC) from January 2013 to December 2014. Demographic data, Complete Blood Picture (CBC), Peripheral Blood Film (PBF), Bone Marrow Aspiration (BMA), immunophenotyping as well as cytogenetic if applicable were evaluated. Result: Forty-two (77.8%) were diagnosed as AML and twelve (22.2%) as ALL. The median age for diagnosis of AML was 43 years. with male to female ratio 1.3:1 while for ALL the median age was 20 years, and male to female ratio was 2:1. Anemia was noted in (90.5%) and (100%) for AML and ALL, respectively. Thrombocytopenia was detected in (83%) for both types. Almost half of AML patients (47%) and (41%) of ALL cases presented with leukocytosis. Blasts were detected in more than two third (74%) of PBF of AML and (75%) in ALL patients. CD13 and CD33 and cyMPO were the most common positive myeloid presenting antigens. However, in ALL B-lymphoid markers CD10 and CD19 were the major positive antigens. Conclusion: AML was most common than ALL in adults, AML was common in middle age while ALL in young age group. Hematology departments require urgent improvement of diagnostic services in Libya in order to ensure good clinical management.