Population-based observational studies have suggested a relationship between psoriasis and hypertension. We performed a systematic review and meta-analysis to better understand the association between psoriasis and hypertension. We systematically searched MEDLINE, EMBASE, and the Cochrane Central Register from 1 January 1980 to 1 January 2012. Two authors independently assessed trial eligibility and quality. We applied the Meta-Analysis of Observational Studies in Epidemiology guidelines in the conduct of this study. We identified 24 observational studies with a total of approximately 2.7 million study participants fulfilling our inclusion criteria. Among them, 309 469 were patients with psoriasis. On the basis of random effects modeling of case–control and cross–sectional studies, the odds ratio (OR) for hypertension among patients with psoriasis was 1.58 [95% confidence interval (CI) 1.42–1.76] compared with the controls. The OR for hypertension among patients with mild psoriasis was 1.30 (95% CI 1.15–1.47) and the OR for hypertension among patients with severe psoriasis was 1.49 (95% CI 1.20–1.86) compared with the controls. Two cohort studies examining incidence of hypertension found that psoriasis was associated with a hazard ratio of 1.09 (95% CI 1.05–1.14) and 1.17 (95% CI 1.06–1.30) for development of hypertension. In a subgroup analysis, patients with psoriatic arthritis also had an increased prevalence of hypertension (OR 2.07, 95% CI 1.41–3.04). Psoriasis and psoriatic arthritis are associated with greater prevalence of hypertension. Patients with severe psoriasis have greater odds of hypertension than those with mild psoriasis.