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Objective The relationship between cerebrospinal fluid (CSF)-venous fistulas (CVFs) and meningeal diverticula (MD) remain insufficiently characterized. This study aimed to characterize MD in confirmed CVF patients, including those at the fistula site and overall burden, to define their imaging features, distribution, and value for CVF localization.Methods In this retrospective two-center study (January 2021–June 2025), consecutive patients with confirmed CVFs were included. Screening of MD was performed on coronal heavily T2-weighted MRI. Leak-level evaluation used CT-/cone beam CT (CBCT)-myelography to assess presence, size, and morphology. The main readers were not blinded to CVF location.Results Among 173 patients (99 women) with 200 CVFs, mean age was 61.7±13.9 years, mean body mass index was 24.9±4.3 kg/m 2, and median Bern score was 6 (IQR 4–8).Patients aged ≥50 years were more prevalent (82%), showed more (9.2±7.6 vs 3.4±4.1, p<0.001) and larger MD (4–15 mm, p<0.001), and higher prevalence of subdural hematomas (40% vs 13%, p<0.05) than those aged <50 years.Patients without MD on MRI (13%) were younger (52.6±15.9 vs 63.0±13.1 years, p<0.001), rarely had multiple (1/23) and no bilateral CVFs. At leak level, MD were the origin of CVF in 80% (159/200), were more frequent and larger in patients aged>50 years (84% vs 54%, p<0.001; 7.2±3.6 vs 5.2±1.8 mm, p<0.001), and predominantly round-ovoid (70%).CVFs mainly arose between T6 and T12 (81%), corresponding to 73% of the largest MD location. CVFs originated in 19% at and in 53% within ±2 bilateral levels around the largest MD, and were right-sided in 66% when the largest MD was right-sided.Conclusions MD were strongly associated with CVFs and were more frequent and larger in older patients. On MRI, MD had limited value for CVF localization, whereas the lower thoracic spine was a more reliable predictor.