Studies on the prevalence of headache in systemic lupus erythematosus (SLE) have shown that it varies from 32 to 78%. The purpose of our study was to determine the prevalence and characteristics of headache in SLE compared with patients with different types of diffuse connective tissue diseases (DCTD) and its relationship with clinical and laboratory manifestations of SLE. We studied patients with SLE (SLE group) and patients with DCTD (control group). All patients were made to answer questionnaire to assess the presence of headache, characterized by at least five episodes of headache during the last year, which was classified according to the International Headache Society criteria. A total of 207 patients were studied, 115 in SLE group and 92 in the control group. The 1-year prevalence of headache was 75.7% in SLE group and 66% in the control group. When the groups were analyzed, 66.1% met the diagnostic criteria for migraine in the SLE group compared with 52.2% in the control group (p=0.04) and 13.9% for tension-type headache in SLE group compared with 16.3% in the control group. The former was the only variable that reached statistical significance comparing the two groups. Both headache and migraine were associated with Raynaud's phenomenon in SLE patients (odds ratio of 2.80, 95% confidence interval: 1.11-7.05, p=0.02 and odds ratio of 2.34, 95% confidence interval: 1.04-5.23, p=0.03, respectively). These results suggest that headache is a common manifestation in SLE and in other DCTD and we cannot exclude the possibility that it may be related to the emotional stress induced by such clinical situations.