Objectives: Measurement of systolic flow velocity (VS), diastolic flow velocity (VD), and resistance index (RI) in internal carotid artery (ACI) in subjects with pseudoexfoliative glaucoma (PEX) and subjects with primary open-angle glaucoma (POAG) to determine the difference that would be in favor of vascular factors as risk factors for origin and progression of pseudoexfoliative glaucoma. Subjects and methods: The research includes 80 subjects divided into two groups. The POAG group consists of 40 subjects with bilateral primary open-angle glaucoma. In the PEX group there are 40 subjects with pseudoexfoliative glaucoma, of which 13 have bilateral lesions, 11 unilaterally in the right eye and 16 subjects in the left eye only. Doppler ultrasound measured VS ACI, VD ACI, and RI ACI on 4 occasions at 6-month intervals. Results: The resistance index showed differences in terms of higher values in the PEX group (P=0.031) than the values measured in the POAG group. Flow velocities in systole and diastole were not statistically significant. Within the PEX group, higher flow velocities were found in systole and diastole in the left eye than in the right. Conclusions: The increased resistance index in the internal carotid artery suggests that vascular risk factors have a role in the development of pseudoexfoliative glaucoma. The results obtained also suggest the existence of a difference in the importance of vascular factors between pseudoexfoliative glaucoma and primary open-angle glaucoma.