The incidence and type of complications appearing following the performance of liver biopsies were analyzed in the first 166 liver transplants in our hospital. The presence of a severe complications was defined if a patient presented hemoperitoneum, pneumothorax, hemothorax, post biopsy infection or symptomatic puncture of abdominal organs other than the liver. Four hundred thirty-eight liver biopsies were carried out in 129 patients with a mean of 3.4 biopsies per patient. The severe complications were observed in 7 (1.6%), all of which were bleeding episodes. Four hemothorax requiring the placement of a thoracic drainage tube were observed. In two cases thoracotomy was required with death occurring in one patient. Three hemoperitoneum were also seen requiring laparotomy in one and transfusion in the remaining two patients. Out of the non transplanted patients, four presented severe complications (0.7%), 50% of which were hemoperitoneum. No patient presented hemothorax and no deaths were reported. The authors conclude that the incidence of severe post liver biopsy complications in transplanted is low, similar to that reported in non transplanted patients. Nonetheless, there does appear to be a higher incidence of bleeding complications in the transplanted patients.