Objective：To explore the prevention measures for thrombus after receiving living donor liver transplantation in children through regulating coagulation function. Methods：Before-after self-controlled study was used among 20 children who had undergone living donor liver transplantation in our hospital. Coagulation function was monitored and analyzed before the operation and on the 1st，3rd，5th，7th d after the operation. Continuous intravenous injection of heparin 5-20 U/（kg·h） and low molecular dextran 5 ml/（kg·d） was administered. Prostaglandin E1 5 ng/（kg·min），was continuously injected for 2 hours and hepatic vascular was expanded 3 times a day. Prothrombin time（PT） was extended 1-2 times than the normal value. Reducing heparin dosages or stopping heparin injection or injecting fresh frozen plasma or doing cryoprecipitate was ad－ministrated if PT lasted too long. Results：Compared with levels before the operation，PT was extended on the 1st d（（18.72±4.40） s，P=0.001） and the 3rd d（（16.96±3.03） s，P=0.043） after the operation；but there was no difference between the 5th d（（16.42±4.75） s，P=0.101） and the 7th d（（15.50±5.94） s，P=0.332）. There was no difference in levels of activated partial throm－boplastin time（APTT） and thrombin time（TT） on the 1st，3rd，5th，7th d after the operation（APTT：before the operation（44.21±24.16） s，the 1st d after the operation（55.74±20.47） s，the 3rd d after the operation （55.19±23.80） s，the 5th d after the operation（54.59±23.84） s，the 7th d after the operation（40.35±12.63） s，F=1.810，P=0.1334；TT：before the operation（19.44±8.29） s，the 1st d after the operation（18.80±4.74） s，the 3rd d after the operation（20.58±4.54） s，the 5th d after the operation（19.81±3.56） s，the 7th d after the operation（18.62±4.16） s，F=0.44，P=0.779）. Significant decrease in fibrinogen level was observed on the 1st d（（1.48±0.54） g/L，P=0.005），the 5th d（（1.37±0.63） g/L，P=0.001） and the 7th d（（1.56±0.46） g/L，P=0.012） but not on the 3rd d（（1.73±0.75） g/L，P=0.071） after the operation. Significant decrease in platelet level was found on the 1st d（107.70±51.82）×109 units/L，the 3rd d（132.00±70.25）×109 units/L，the 5th d（175.70±73.89）×109 units/L and the 7th d（158.40±60.83）×109 units/L after the liver transplantation（F=15.43，P=0.000）. No case of serious blood clotting disorders and thrombosis was observed. Conclusion：Coagulation function can be regulated through medicine after the operation in pediatric recipients of live donor liver transplants. The purpose of the regulation is to control the bleeding tendency，prevent the hypercoagulable state，avoid thrombosis. Meanwhile，color Doppler examination is an effective method for diagnosis of hepatic vascular thrombosis.