Ankylosing spondylitis is a typical, very heritable incendiary joint inflammation, influencing principally the spine and pelvis. Inflammatory arthritis in ankylosing spondylitis causes pain and stiffness and progressively leads to new bone formation and ankylosis (fusion) of affected joints. Systemic lupus erythematosus (SLE, lupus) is a highly complex and heterogeneous autoimmune disease that most often afflicts women in their child-bearing years. It is characterized by circulating self-reactive antibodies that deposit in tissues, including skin, kidneys, and brain, and the ensuing inflammatory response can lead to irreparable tissue damage. There are few reports of coexistence of Ankylosing spondylitis and Systemic lupus erythematosus which firmly emphasis on an overlap phenomenon between these two disorders. A 30 year old woman was admitted to our hospital due to signs of butterfly-shaped rash on her cheeks, which became prominent after exposure to sunlight and severe inflammatory low-back pain. About ten year earlier, AS had been diagnosed and treatment started with non-steroidal anti-inflammatory drug (NSAID). To the best of our knowledge, the present case is one of 10 reported cases of coexistence of these two disorders in English literature. The coexistence of these two diseases with different genetic backgrounds and clinical symptoms may implicate the importance of shared environmental factors.