This is a case series which report the clinical results of decompressive craniectomy in 4 patients with dilated pupils secondary to traumatic brain injury and postoperative edema. Between 2011 and 2012, four patients, 3 males and 1 female, aged between 35 and 64 with mean age of 50.1 ± 8.9 years, underwent decompressive craniectomy due to brain traumatic edema. The follow up period ranged between 1 to 6 months. All patients had Glasgow coma score (GCS) of 3-4 at admission, and the duration of pupils being mydriatic was less than 20 minutes before the operation. All patients had moderate disability with GCS of 4 after the operation. Decompressive craniectomy can be a life-saving procedure which provides a better outcome in patients with dilated pupils secondary to brain trauma injury and postoperative edema with timing of less than 20 minutes. However, the small number of the patients in this study is the main limitation to the accuracy of the results, and more studies with larger number of patients are warranted to evaluate the efficiency of decompressive craniectomy in patients with dilated pupils.