ObjectivesTo assess the association between overactive bladder syndrome (OAB) and the metabolic syndrome (MetS).Patients and MethodsA population‐based study was conducted to compare OAB patients with age‐, sex‐ and ethnicity‐matched control subjects regarding the prevalence of the parameters of the MetS, with respect to obesity, hyperlipidemia, hypertension and diabetes mellitus. The characteristics of the OAB population were assessed. Adjusted odds ratios (OR) were calculated by logistic regression.Results110 024 OAB patients and 220 455 controls. were identified. OAB was associated with a higher prevalence of MetS (35.4% vs. 27.5%, p < 0.001). The fully adjusted OR for MetS in patients with OAB compared to controls was 1.44; 95% confidence interval (CI) 1.42−1.46; p < 0.001. Among metabolic parameters, obesity was found to be the strongest factor associated with OAB (OR 1.55, 95% CI 1.53−1.58, p < 0.001), and higher high‐density lipoprotein cholesterole levels (>50) had a protective effect on the risk of OAB (OR 0.75, 95% CI 0.73−0.76, p < 0.001).ConclusionsData from this cohort suggest that OAB is positively associated with MetS. Clinicians approaching patients with OAB should be aware of this association. A multimodal treatment focusing on the MetS may be considered in these patients.