Twenty-two adult patients with acute nonlymphocytic leukemia (ANLL) were analyzed. There were 15 males (68%) and 7 females (32%). Their median age was 42 years. Thirty-six percent had acute myelomonocytic leukemia (M4), and 46% had acute monocytic leukemia (M5), according to the French-American-British classification. Of 17 patients who received intensive combination chemotherapy, 47% achieved complete remission. Of the subgroup of 14 new and previously untreated patients, the complete remission rate was 57%. The rest of the patients died of septic complications. We report an increased ratio of M4 and M5 in ANLL in Saudi Arabia and an increased rate of severe septic and fungal complications.