Abstract: Objective: The purpose of the study was to discuss the application value of spectral CT in preoperative imaging evaluation of the living donor's vessels in pediatric liver transplantation. Methods: Preoperational spectral CT scan was performed for 30 living donors. CTA were performed, both monochromatic and combined energetic, on their hepatic artery and vein, also the portal vein. The donor's total volume and the planning cutting part was measured respectively and compared with the real replanting liver volume. Result: The monochromatic CTA imaging quality of the liver vessels at 50 ke V is better than the combined one (P ＜ 0.001). And the anatomical variation of the donor's liver vessels could be shown very clear by CTA. Conclusion: As one of the methods of the preoperative evaluation of the living donor's liver in pediatric liver transplantation, the monochromatic CTA could show high quality contrast image between the vessels and the soft tissues, and guarantee the quality of vessel reconstruction image and the accuracy of assessment.