We describe a 13-year-old female patient with systemic lupus erythematosus (SLE) who presented with acute transverse myelitis (ATM) in the course of SLE. IgG and IgM anticardiolipin antibodies (aCL) were positive at moderate titers. Magnetic resonance imaging (MRI) of the thoracic spine demonstrated decreased signal intensity and diffuse edema of the spinal cord from T2 to T6 on T1-weighted images. Dramatic clinical improvement of the neurologic impairment was noted a few days after high dose intravenous (IV) methylprednisolone (MP) and cyclophosphamide (Cy). Herein we further emphasize the benefit of IV MP and Cy in ATM and the relationship between ATM and antiphospholipid antibodies (aPLA) in SLE.