BACKGROUND Chronic cerebrospinal venous insufficiency (CCSVI) has been reported in multiple sclerosis (MS) yet its significance in relation to cognitive function is undetermined.This study measured the association between the presence and severity of CCSVI and cognitive impairment in patients with MS. METHODS CCSVI was assessed using extra-cranial and trans-cranial Doppler sonography in 109 MS patients (79 with relapsing-remitting, 23 with secondary-progressive and 7 with primary-progressive disease subtype). A subject was considered CCSVI-positive if ≥2 venous hemodynamic criteria were fulfilled. The Minimal Assessment of Cognitive Function in MS (MACFIMS) battery was administered assessing the full spectrum of cognitive domains known to be affected by MS. Depression was quantified using the Beck Depression Inventory Fast Screen (BDIFS). Partial correlations, analysis of variance (or covariance) and linear regression were used to examine the hypothesis that CCSVI status is related to cognition or depression after controlling for education and gender. RESULTS There were 64 (58.7%) patients who were considered CCSVI-positive. The regression models predicting venous hemodynamic insufficiency severity score were not statistically significant for any of the MACFIMS predictor variables. The analysis of variance tests showed a significant effect of CCSVI-positive diagnosis on cognitive ability in only one of the 10 MACFIMS outcomes, and that one was in the opposite direction of the tested hypothesis. There was no correspondence between CCSVI diagnosis and depression, as measured by the BDIFS. CONCLUSIONS We find no evidence of an association between the presence and severity of CCSVI with cognitive impairment and depression in patients with MS.