Objective To investigate the significance of hepatic arterial reconstruction on the model of 40% small-for-size orthotopic liver transplantation in rats. Methods Modified two-cuff technique was applied to establish a rat model of 40% orthotopic liver transplantation. A total of 240 Sprague Dawley (SD) rats were randomly divided into 2 groups: reconstructive artery group and non-reconstructive artery group. One week survival rate was observed. Main indexes of liver function, histology and the expression of proliferative cell nuclear antigen (PCNA) of liver graft （by immunohistochemical method） were detected on day 1, 2, 4 and 7 after transplantation, respectively. Results One week survival rates of reconstructive artery group and non-reconstructive artery group were 65.0% (13/20) and 50.0% (10/20) respectively (Pgt;0.05). Alanine aminotransferase (ALT) and total bilirubin (TB) began to elevate from day 1 and peaked on day 2 after surgery in two groups. ALT in non-reconstructive artery group on day 2 and 4 were significantly higher than that in reconstructive artery group (P＜0.05). TB in non-reconstructive artery group on day 2 and 7 were significantly higher than that in reconstructive artery group (P＜0.05). Histological findings indicated that more diploid and polyploid hepatocytes and more gently dilation of central veins and hepatic sinusoids could be seen postoperatively in reconstructive artery group. The expression of PCNA of liver graft peaked on day 2 after surgery. The expression of PCNA of reconstructive artery group was higher on day 1 (P＜0.01) and lower on day 7 than that of non-reconstructive artery group after operation (P＜0.05). Conclusions Arterial reconstruction can improve liver function of liver grafts after small-for-size orthotopic liver transplantation, alleviate the histological changes and promote the regeneration of liver grafts quickly.