The present study was undertaken to examine the clinical characteristics of patients with major affective disorders and comorbid migraine. Patients (n = 102) with an index episode of either major depression or mania were interviewed with a semi-structured interview based partly on DSM-IV criteria and partly on Akiskal's criteria for affective temperaments. Compared to the patients without migraine (n = 49), the patients with comorbid migraine (n = 53) had a higher frequency of bipolar II disorder (43% vs. 10%), a lower frequency of bipolar I disorder (11% vs. 33%), an approximately equal frequency of unipolar depressive disorder (45% vs. 57%) and a higher frequency of affective temperaments (45% vs. 22%). The migraine patients also had a greater number of anxiety disorders (3.0 vs. 1.9) and a higher frequency of panic disorder and agoraphobia. Gender distribution, age, age at onset of first affective episode, number of previous episodes and symptoms during depressive episodes were similar in both groups. Based on these findings it is suggested that the presence of migraine may be used to delineate a distinct subgroup of the major affective disorders.