Background Introperitoneal hemorrhage is one of the mos t common complications of radiofrequency (RF) ablation of hepatic tumors. This study was designed to investigate the reason and management of intraperitoneal h emorrhage occurred during or after percutaneous RF ablation of hepatic tumors. Methods Three hundred and fifty-six patients with hepatic tumo rs have been treated at 592 procedures of ultrasound guided RF ablation. Intrap eritoneal hemorrhage occurred in 5 patients (0.8%). The reasons and management of intraperitoneal hemorrhage in these 5 cases were retrospectively analyzed. Results Two patients with liver metastasis and one hepatocellul ar carcinoma (HCC) patient suffered from hemorrhage during the RF treatment. Tw o patients with recurrent HCC after surgery developed hemorrhage 20 minutes or 4 hours after RF treatment. One case of hemorrhage was due to the inappropriate electrode positioning induced liver laceration while treating a 1 cm liver metas tasis near the liver capsule. One was due to the injury of a small vessel by th e RF needle in another liver metastasis patient. Three cases were due to tumor rupture with two cases induced by cough or position change after treating large protruding HCC lesions. Four (80%) of the 5 cases of hemorrhage were rapidly id e ntified by ultrasound. The causes and sites of bleeding during the RF treatment in three cases were confirmed through ultrasound, which were successfully treat ed using RF coagulation to achieve hemostasis of the bleeding site. Two patient s with post-ablation hemorrhage recovered in one hour and 24 hours, respectivel y after given blood transfusion and other conservative measures. No surgical in tervention was required. Two patients died of wide spread metastasis 23-36 mon ths afterwards and the other three patients have lived for 18-25 months to date . Conclusions It is important to perform close monitoring during and after RF ablation in order to identify intraperitoneal hemorrhage in time. RF ablation of the bleeding sites was a simple and effective management when the bleeding site could be confirmed by ultrasound. The hemorrhage due to the rupt ure of large and protruding liver tumors could be serious and should be consider ed as contraindication for RF treatment. Background Introperitoneal hemorrhage is one of the mos t common complications of radiofrequency (RF) ablation of hepatic tumors. This study was designed to investigate the reason and management of intraperitoneal h emorrhage occurred during or after percutaneous RF ablation of hepatic tumors. Methods Three hundred and Fifty-six patients with hepatic tumo rs have been treated at 592 procedures of ultrasound guided RF ablation. Intrap eritoneal hemorrhage occurred in 5 patients (0.8%). The reasons and management of intraperitoneal hemorrhage in these 5 cases were retrospectively analyzed. Results Two patients with liver metastasis and one hepatocellul ar carcinoma (HCC) patient suffered from hemorrhage during the RF treatment. Tw o patients with recurrent HCC after surgery developed hemorrhage 20 minutes or 4 hours after RF treatment. One case of hemorrhage was due to the inappropriate electrode positioning induced liver laceration while treating a 1 cm liver metas tasis near the liver capsule. One was due to the injury of a small vessel by th e RF needle in another small vessel by th e RF needle in another small vessel by HCC lesions. Four (80% Of the 5 cases of hemorrhage were rapidly id e ntified by ultrasound. The causes and sites of bleeding during the RF treatment in three cases were confirmed through ultrasound, which were successfully treated ed using RF coagulation to achieve hemostasis of the bleeding site. Two patient s with post-ablation hemorrhage recovered in one hour and 24 hours, eachl y after given blood transfusion and other conservative measures. No surgical in tervention was required. Two patients died of wide spread metastasis 23-36 mon ths afterwards and the other three patients have lived for 18-25 months to date. Conclusions It is important to perform close monitoring during and after RF ablation in order to identify intraperitoneal hemorrhage in time. RF ablation of the bleeding sites was be simple and effective management when the bleeding site could be confirmed by ultrasound. The hemorrhage due to the rupt ure of large and protruding liver tumors could be serious and should be consider ed as contraindication for RF treatment .