Priapism is a rare complication of hematological diseases. Among leukemia, it is most frequently seen in patients with chronic myeloid leukemia, due to the high leukocyte counts that these patients achieve. We report a 22 years old male who presented with a priapism lasting more than 24 hours. Thirty six hours after admission and subsequent to a leukopheresis, penile relaxation was obtained. Despite good hematological response to therapy, an extensive penile and uretral necrosis, associated to an Acinetobacter infection, ensued between the fourth and fifth day of admission, that required surgical treatment.