To assess the association between pseudotumor cerebri (PC) andsystemic lupus erythematosus (SLE), and to seek a pathogenic mechanism that may elucidate the appearance of PC in patients with SLE.Original English articles having the terms SLE, PC, or benign intracranial hypertension in their titles were identified by Medline search. In addition we report three new patients with this association.Thirteen articles were found and 21 patients were analyzed.Of the reported 21 patients, 18 were previously reported and 3new patients with coexisting PC and SLE are described. The clinical characteristics of the patients is presented. Patients with PC and SLE generally had a more severe course of SLE; renal involvement occurred in 79%, massive proteinuria in 47%, and hematologic abnormalities were detected in a third. A hypercoagulable state manifest by either recurrent thromboembolic events or a high anti-cardiolipin antibody titer was detected in 58% of the patients described.The association of PC and SLE is probably not coincidental. The high prevalence of serologic or clinical evidence of a hypercoagulable state suggests that microscopical thromboembolic events play a role in the genesis of PC.