Objective:To analyze hepatic hemodynamic parameters detected by Doppler ultrasound (DU) of uncomplicated children who underwent left lateral segment(LLS) LDLT (LLS-LDLT), explore their change trends over time and determine the normal reference intervals.Methods:This retrospective study involved the data from 261 pediatric LLS-LDLT cases in Tianjin First Central Hospital from June 2014 to January 2018. Hemodynamic parameters included peak systolic velocity (PSV), end diastolic velocity (EDV), resistivity index (RI), and pulsation index (PI) of hepatic artery (HA), and portal vein velocity (PVV) during intra-operative and on the 1st, 3rd, 5th and 7th days after operation were collected. Among whom, 232 cases with uncomplicated and normal recovery were finally involved in our study, with 200 cases who were collected from June 2014 to August 2017 as test group. Those collected from September 2017 to January 2018, totally 32 cases were set as validation group. The change trends and normal ranges of hemodynamic parameters over time were analyzed in test group, and the results were further tested in the validation group.Results:In the test group, PSV HA, EDV HA showed a similar change trend at one week after surgery, with an overall decrease-rise trend; RI HA, PI HA also changed similarly with an overall rise-decrease trend. PVV at surgery was lower than at all time points after surgery. In addition, this study provided the normal reference intervals of hemodynamic parameters for LDLT patients at early postoperative period, which at intra-operation they were PSV HA 18.4-98.3 cm/s, EDV HA 0-43.3 cm/s, RI HA 0.41-1.0, PI HA 0.51-2.0, PVV 19.0-83.7 cm/s. Within 1 week after surgery: PSV HA 21.0-97.7 cm/s, EDV HA 0-32.7 cm/s, RI HA 0.47-1.0, PI HA 0.62-2.0, PVV 23.0-92.0 cm/s. By using those results, the coincidence rate of Doppler parameter change trend was 84.3%(27/32), 84.3%(27/32), 78.1%(25/32), 78.1%(25/32), 87.5%(28/32) for PSV HA, EDV HA, RI HA, PI HA, PVV in the validation group, respectively. As for the normal reference intervals of blood flow parameters, RI HA and PI HA in one case in the validation group were lower than the lower limits of the normal reference intervals, accounting for 3.1% of the total. PSV HA in two cases was lower than the lower limit of normal reference interval, accounting for 6.2% of the total. Conclusions:The hepatic hemodynamic in post-transplanted children detected by DU has specific changing trends and normal ranges, which provides valuable reference values for ultrasonologists and pediatric transplant clinicians.