- Background Hidradenitis suppurativa (HS) is a chronic recurrent inflammatory disease affecting skin that bears apocrine glands. Only anecdotal reports and a few small studies have demonstrated a possible association between HS and depression, but these studies were uncontrolled or were based on small sample sizes. To the best of our knowledge, the association between HS and other psychiatric disorders has never been investigated. Objectives To investigate the association between HS and psychiatric disorders: depression, anxiety, psychoses, schizophrenia and bipolar disorder. Methods A cross-sectional study was conducted utilizing the database of Clalit Health Services (over 4 100 000 patients). Case patients were defined as having HS when diagnosed by a dermatologist. Control patients without HS were age and gender matched in a 2 : 1 manner. The proportions of patients with psychiatric diseases were compared between patients with and without HS. The association between HS and psychiatric diseases was assessed in multivariate models using logistic regression analyses. Results The study included 3207 patients with HS and 6412 age- and gender-matched controls. Depression was diagnosed in 5.9% of patients with HS vs. 3.5% of patients without HS (P < 0.001). Anxiety was diagnosed in 3.9% of patients with HS vs. 2.4% of patients without HS (P < 0.001). These associations were significant after controlling for the confounders age and gender (Depression: OR = 1.7, 95% CI: 1.4–2.1; Anxiety: OR = 1.7, 95% CI: 1.3–2.1). Conclusions Hidradenitis suppurativa was associated with depression and anxiety. Dermatologists treating patients with HS should be aware of this important association.