Objective Based on clinical features and imaging data， the influencing factors of atherosclerotic stenosis in the intracranial segment of the vertebral artery were explored. Methods This study adopted a retrospective analysis approach. It selected 216 patients who either visited the hospital because of symptoms like dizziness and vertigo associated with posterior circulation ischemia or underwent routine cerebrovascular assessment. These patients simultaneously completed brain-cervical artery ultrasound and CT Angiography （CTA） examinations between January 2021 and June 2025. According to the diagnostic criteria of CTA， patients with a stenosis rate of ≥ 50% in the intracranial segment of the vertebral artery were included in the case group （62 cases）， whereas those without stenosis or with a stenosis rate < 50% were included in the control group （154 cases）. The clinical data， ultrasound hemodynamic parameters， and plaque characteristics of the two groups were compared. Variables with P < 0.05 in the univariate analysis were incorporated into the multivariate logistic regression model to screen out independent influencing factors. Results The peak systolic velocity and the end-diastolic velocity of the vertebral artery in the case group were significantly higher than those in the control group （P < 0.05）. Meanwhile， the diameter of the vertebral artery in the case group was significantly smaller than that in the control group （P < 0.05）. The proportion of patients with a smoking history， hypertension， diabetes， and eccentric plaques in the case group was significantly higher than that in the control group （all P < 0.05）. The levels of low-density lipoprotein and plaque burden in the case group were also significantly higher than those in the control group （P < 0.05）. Single-factor analysis indicated that there were statistically significant differences in the above indicators between the two groups （all P < 0.05）. The variables with significant meanings from the single-factor analysis were then included in the multivariate Logistic regression analysis. The results demonstrated that having a smoking history （OR = 3.340， 95%CI： 1.258 - 8.865）， elevated low-density lipoprotein levels （OR = 2.392， 95%CI： 1.233 - 4.639）， hypertension （OR = 2.630， 95%CI： 1.108 - 6.242）， diabetes （OR = 2.863， 95%CI： 1.302 - 6.296）， eccentric plaques （OR = 2.649， 95%CI： 1.398 - 5.018）， and large plaque burden （OR = 2.482， 95%CI： 1.267 - 4.861） were all independent influencing factors of atherosclerotic stenosis of the intracranial segment of the vertebral artery （all P < 0.05）. Based on this， a model was constructed as follows： logit（P） = 0.685 + 1.206 × smoking history + 0.872 × increase in low-density lipoprotein level + 0.967 × co-occurrence of hypertension + 1.052 × co-occurrence of diabetes + 0.974 × eccentric plaque + 0.909 × large plaque load. When logit（P） > 0.648， the AUC is 0.891 （95%CI： 0.842 - 0.930）， χ² = 15.320， and the sensitivity and specificity are 83.87% and 83.12% respectively. Conclusions This study demonstrates that a history of smoking， hypertension， diabetes， elevated LDL-C levels， eccentric and high-load plaques are independent influencing factors for stenosis of the intracranial segment of the vertebral artery. Based on these indicators， a logistic model was successfully constructed. This model fits well and has a high predictive value for atherosclerotic stenosis of the intracranial segment of the vertebral artery. Clinically， for patients with the aforementioned characteristics， more imaging screening and risk assessment of the intracranial segment of the vertebral artery should be enhanced.