We reported a 31-year-old woman with epilepsia partialis continua (EPC) whose epileptic focus was delineated by PET. Neurologic examination revealed EPC in the face around the corner of her mouth, her thumb and forefinger on the left, slight exaggeration in the left biceps brachii reflex, and the digiti quiniti sign on the left. Laboratory tests showed pancytopenia, positive anti-nuclear and anti-DNA antibodies and decreased levels of serum complements, being consistent with systemic lupus erythematosus (SLE). Electroencephalogram showed paroxysmal discharges over the right frontoparietal region. PET with 2-18F-fluoro-2-deoxy-D glucose (FDG) clearly demonstrated a hypermetabolic area in the right frontoparietal cortex. T2-weighted images in MRI revealed reversible high signal intensity area in the right insula, postcentral gyrus and angular gyrus, while there were no abnormal findings in T1-weighted images with or without Gd-DTPA. There are only a few reports of EPC with the epileptic focus delineated by PET. Since a focal increase in glucose metabolism observed in them as well as in the present patient is a consistent indicator of the epileptic focus, the PET study is likely to provide significant information available not only for the diagnosis but also for the treatment of the condition. Finally, to our knowledge, this is the first patient with SLE presenting EPC. It is important to realize that vasculopathy associated with SLE may cause EPC and brain lesions with reversible high signal intensities shown by MRI.