We aimed to investigate whether and how venous disruption was related to white matter damage in cerebral small vessel disease(CSVD) patients. SWI was used to investigate venous disruption. Free water elimination DTI model was used to analyze interstitial fluid fraction(fraction of free water, fFW) and white matter integrity(tissue fractional anisotropy, FAt). In 104 CSVD patients, venous disruption was associated with FAt, and the effect was mediated by fFW. This relationship was independent of arterial cerebral blood flow. In conclusion, we discovered the venous disruption - increased interstitial fluid - white matter damage link in CSVD patients.