【Abstract】 Objective To explore the value of standardized multislice spiral CT portography for the liver fibrosis in piglets. Methods 16 Chinese healthy miniature piglets were prospectively used to make liver fibrosis models by carbon tetrachloride. On 0, 5th, 9th, 16th and 21st week after the beginning of modeling, all normal laboratory animals were treated with CT dynamic contrastenhanced scans, respectively. Time to peakenhancement (TTP) obtained from dynamic scan was used as standard scan time to perform CTP. Spleen vein diameter (SVD), portal vein diameter (PVD) and superior mesenteric vein diameter (SMVD) were measured on CTP.Results TTP, SVD, PVD and SMVD increased with the progress of liver fibrosis (r=0.234 to 0.613, all p＜0.05). MannWhitney tests demonstrated that SVD could classify liver fibrosis between stage 0 and 14. Both SVD and PVD could discriminate liver fibrosis between stage 01 and 24, between stage 02 and 34, and between stage 03 and 4 (all p＜0.01). SMVD could not differentiate between any two stages (all p＞0.05). Receiver operating characteristic analysis (ROC) illustrated that SVD could classify the stage ≥1 (area under curve [AUC]=0.893).AUC of SVD was larger than that of PVD for classifying stage ≥2, ≥3 and 4 (AUC=0.789 to 0.829).Conclusion Diameter of portal system could stage liver fibrosis, and SVD can be best used to classify this disease.