Many patients with ankylosing spondylitis (AS) are often misdiagnosed with other conditions when they first seek medical attention and are not properly treated in a timely manner. Of all the misdiagnoses, the largest number of patients are misdiagnosed with lumbar disc herniation, and at the same time, this group of patients takes the longest time to be diagnosed, which seriously affects their treatment. Therefore, it is hoped that fellow patients will be more vigilant in diagnosing patients with low back pain so as not to misdiagnose patients with AS. Ankylosing spondylitis (AS) is a chronic, progressive inflammatory disease of the spine.AS often causes lumbosacral pain after invading the spine and sacroiliac joints. Many patients seek treatment for this condition, but for a number of reasons, including the lack of specificity of clinical symptoms, poor pathogenetic and laboratory results, and the lack of imaging of sacroiliac arthritis in patients with early-stage AS, patients with AS ultimately take 5-10 years before a definitive diagnosis is made. Reasons why AS patients are misdiagnosed with lumbar disc herniation on their first visit Most patients choose to visit physical therapy, orthopedics and neurology instead of rheumatology on their first visit for lumbosacral pain. The first thing the receiving physician thinks of when a patient complains of low back pain is a lumbar disc herniation. In addition, some patients had only low back pain without spondylolisthesis at the time of their first visit, while others had actually suffered from lumbar disc herniation before, and some had even undergone surgical treatment for it. In order to reduce the rate of misdiagnosis of AS at the initial consultation, doctors should be more aware of ankylosing spondylitis as a disease and be able to think of AS when diagnosing patients with low back pain, so that relevant tests can be improved to clarify the diagnosis of suspected patients, and the referral procedure should be further improved, and it is hoped that the suspected patients can be followed up by rheumatologists as early as possible for further investigation or treatment.