Acute calcific tendinitis of the longus colli muscle, which is also known as retropharyngeal calcific tendinitis, is an under-recongnized cause of acute cervical pain produced by an inflammation of the longus colli muscle. Acute calcific tendinitis of the longus colli muscle is a rare benign condition which is characterized by acute sore throat, neck pain and stiffness, dysphagia, odynophagia and a limited range in the cervical spine. This condition can easily be overlooked or misdiagnosed because of its rather non-specific presentation and rare occurrence. The differential diagnosis includes a retropharyngeal abscess, meningitis, infectious spondylitis and herniated disc in the cervical spine. Knowledge of the clinical and imaging findings can prevent a misdiagnosis and inappropriate procedures. We report a case of acute calcific retropharyngeal tendinitis with a reviews of the related literatures.