Background Introperitoneal hemorrhage is one of the most common complications of radiofrequency (RF) ablation of hepatic tumors. This study was designed to investigate the reason and management of intraperitoneal hemorrhage occurred during or after percutaneous RF ablation of hepatic tumors.Methods Three hundred and fifty-six patients with hepatic tumors have been treated at 592 procedures of ultrasound guided RF ablation. Intraperitoneal 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 hepatocellular carcinoma (HCC) patient suffered from hemorrhage during the RF treatment. Two 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 metastasis near the liver capsule. One was due to the injury of a small vessel by the 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 identified by ultrasound. The causes and sites of bleeding during the RF treatment in three cases were confirmed through ultrasound, which were successfully treated using RF coagulation to achieve hemostasis of the bleeding site. Two patients with post-ablation hemorrhage recovered in one hour and 24 hours, respectively after given blood transfusion and other conservative measures. No surgical intervention was required. Two patients died of wide spread metastasis 23-36 months 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 rupture of large and protruding liver tumors could be serious and should be considered as contraindication for RF treatment.