This study sought to examine whether mood, anxiety, and obsessive-compulsive spectrum disorders have unique (comorbidity-independent) associations with suicidal thoughts and behaviors in an acute psychiatric population.Patients (N = 498) were evaluated during admission to a partial hospital. Semi-structured interviews were used to assess current psychiatric diagnoses and past-month suicidal ideation and suicidal behaviors (e.g., suicide attempts).After adjusting for age, gender and other psychiatric disorders, body dysmorphic disorder (BDD) had a significant association with suicidal ideation (odds ratio [OR] = 6.62; 95% CI, 1.92-22.79) and suicidal behaviors (OR = 2.45; 95% CI, 1.05-5.71). Similarly, major depressive episode was associated with suicidal ideation (OR = 3.00; 95% CI, 1.95-4.63) and suicidal behaviors (OR = 2.11; 95% CI, 1.12-3.98). When unipolar and bipolar depression were analyzed separately, unipolar depression was associated with suicidal ideation (OR = 1.82; 95% CI, 1.20-2.74), but not suicidal behaviors, whereas, bipolar depression was associated with suicidal ideation (OR = 2.71; 95% CI, 1.36-5.40) and marginally with suicidal behaviors (OR = 2.02; 95% CI, 0.99-4.13). Anxiety disorders, obsessive-compulsive disorder, and posttraumatic stress disorder were unrelated to suicidality in this sample after controlling for comorbid disorders.Cross-sectional design and a relatively small sample for analyses of low base-rate conditions.Major depressive episode and BDD are unique markers of suicidality in an acute psychiatric setting. BDD is a common but often underdiagnosed condition, and clinicians should be aware of high rates of suicidality among these patients.