Hemophagocytic syndrome (HPS) is an unusual but severe illness associated with a variety of infections, as well as genetic, malignant tumors, and autoimmune diseases. We report an 11-year-old girl with systemic lupus erythematosus and nephritis who developed HPS associated with Epstein-Barr virus reactivation. In our patient, the onset of reactive HPS might be related to immunosuppressive treatment during the course of lupus nephritis.