Objective To measure the diameters of the portal vein and abdominal aorta of the normal adult in Gansu Province by Multi-detector Row Spiral CT, and determine the normal CT scale of portal vein and abdominal aorta of adult. Methods Retrospective analysis 300 normal cases that were performed enhanced abdomen CT in the First Hospital of Lanzhou University from February 2014 to April 2015. They were equally assigned to 3 groups according to their age (A group:18—39years,B group:40-59 years,C group:be equal or greater than 60 years;50 females and 50 males in each group). Measurements were done on 3D reconstruction image with precise landmarks, and these data were statistically analyzed by SPSS22.0. Results There were significant differences in the diameters of the left portal vein between group A and group C(P<0.05), and the diameters of the main portal vein were significantly diffrent between group A and group C, group B and group C(P<0.05), and the diameters of abdominal aorta and R3 differed significantly among each group(P<0.01). The diameters of left portal vein,right portal vein,main portal vein, and abdominal aorta differed significantly among the genders(P<0.05). Conclusion The diameters of main portal vein and abdominal aorta differed significantly among the age and genders. Imaging standard is provided for Gansu Province adult in early diagnosis of liver or portal vein disease．