Background Cerebral venous sinus thrombosis(CVST) is a special form of stroke with multiple causes and risk factors.However,there are still a portion of cases with unknown reasons.The aim of this study was to investigate the relationship between internal jugular vein(IJV) abnormalities and the development of CVST. Methods A total of 51 CVST patients and 30 healthy controls were enrolled.The diameter,the maximum velocity (Vmax) and the reflux time in bilateral IJVs were measured by color Doppler flow imaging(CDFI).The paired t test was used to compare the numeric values between the bilateral IJVs.The Pearson chi-square test was used to evaluate the relationship between IJV abnormality and CVST,IJV abnormality and IJV reflux,respectively. Results Among the 51 CVST patients,20(39%) patients were with normal IJV and 31(61%) patients were with abnormal IJV.The types of IJV abnormality included annulus stenosis 19 cases(61%),hypoplasia 9 cases(29%), thrombosis 2 cases(7%) and anomalous valve 1 case(3%).In patients with unilateral IJV abnormality,the minimum diameter of the IJV on the lesion side was significantly smaller than that of the contralateral side(P<0.0001).When compared with contralateral side,the Vmax of the lesion side with unilateral annulus stenosis was significant higher, however,it was obvious lower in patients with unilateral hypoplasia(P<0.05).Furthermore,among 27 cases with unilateral IJV abnormality,all the CVST occurred on the same side as the IJV lesions. Conclusion IJV abnormality closely correlated with the development of CVST,which is a newly identified risk factor for CVST.