Background: Retropharyngeal calcific tendonitis is defined as an uncommon and self-limiting inflammatory process of the superior oblique tendons of the longus colli muscle. It is considered as one of the differential diagnosis of retropharyngeal fluid collection. Furthermore, it causes neck pain resulting in limitation of the range of motion due to calcification of longus colli muscle and accumulation of sterile effusions. It is very important to have a definitive diagnosis by using computed tomography (CT) because the symptoms of retropharyngeal calcific tendonitis can resemble other serious conditions such as retropharyngeal abscess, thus it will affect the management plan. Retropharyngeal calcific tendonitis does not require surgical treatment; it is treated medically using non-steroidal anti-inflammatory medications. On the other hand, retropharyngeal abscess required incision and drainage. In this study, we discuss one case of retropharyngeal calcific tendonitis complicated by retropharyngeal abscess, discussing key radiologic features, and treatment options.