Objective To sum up experience and lessons learnt from liver separation in two thoracoventropagus twins. Method By preoperative imaging it was verified that the two twins of thoracoventropagus named as AB and CD respectively having independent portal hepatic system and the digestive tract.Intraoperatively a separation line was delineated between the porta hepatis,the second porta hepatis.Liver parenchyma of the AB conjoined twin was separated under local blood control with both sides of the seperation line.Intraoperative bleeding was about 10ml,liver rough surface was suctured together,after ligation or suturing of blood vessels and bile ducts.The livers of CD conjoined twin were separated with blocking the first hepatic hilum firstly,and partial hepatic vascular exclusion secondly by part of the liver pressed with finger.There was intraoperative bleeding of about 200 ml. Results The two cases of conjoined twins were separated successfully,and there was no bile leakage,liver failure and infection.A and B are alive and well.D died of lung infection 78 days later.C died of lung and cavitas thoracis infection 9 months later. Conclusion Liver separation is feasible in a thoracoventropagus with independent porta hepatis system.Partial blocking of hepatic vasculature occlusion,in stead of portal triad clamping is preferred.During the separation of hepatic parenchyma finger press for the control of local hepatic blood flow is not always reliable.