We describe 2 patients with systemic lupus erythematosus (SLE) and high grade atrioventricular (AV) block. In one patient anti-Ro antibodies were positive. This antibody has been associated with congenital complete heart block in children of mothers with SLE; however, its role in adult high grade AV block is not clear. We reviewed the 8 published cases of adults with SLE and high grade AV block. The possible mechanisms that could be implicated in the pathology of high grade AV block are discussed.