Objective To investigate the diagnostic value of susceptibility weighted imaging (SWI)semiquantitative assessment of pathological vascularity in grading cerebral gliomas.Methods Images of thirty-six patients with gliomas(1 5 low-grade and 21 high-grade gliomas)were obtained before therapy.Standard clinical MR imaging and SWI were performed at GE 3.0T scanner.All SWI postprocessed images were reviewed independently by two neuroradiologists and the number of vessels in tumor region were scored. Tumor were graded according to the World Health Organization classification.Results In 1 5 cases of low-grade glioma,semiquanti-tative assessment of pathological vascularity scored 0 in 6 cases,1 in 9 cases.In 21 cases of high-grade gliomas,semiquantitative as-sessment of pathological vascularity scored 2 in 18 cases,3 in 2 cases,1 in 1 case.There was a statistical significance between low-grade and high-grade gliomas(Z =-5.327,P <0.05).The grade of intratumoral pathological vascularity detected on SWI was asso-ciated with tumor grade.Conclusion It is usefull that SWI semiquantitative assessment of pathlogical vascularity in grading cerebral gliomas between low-grade and high-grade.