Neck pain is a common musculoskeletal disorder. It can be disabling, and constitutes a high health and economic burden. A large majority of neck pains are of mechanical origin. There has been a growing research interest on optimal interventions but there are no ‘gold standards’. Spinal manipulation a form of manual therapy is often used in clinical practice to treat individuals with neck pain.However, in recent time manipulation applied directly to the cervical region has come under close scrutiny because of the potential risk of cervical arterial dysfunction. On the other hand, there is growing evidence for the use of thoracic spine manipulation in treating neck pain. Despite the relatively large number of randomized controlled trials carried on its effectiveness, the evidence of the effectiveness of thoracic manipulation in treating neck pain has been described as inconsistent and inconclusive. Therefore, this systematic review critically appraised, synthesized, and provides a clearer and more accurate overall assessment on the effectiveness of thoracic manipulation in reducing pain and disability in adults with mechanical neck pain.