Neck-shoulder-upper extremity pain (NSUEP) is a frequently occurring clinical constellation of syndromes. However, its etiology is complicated, and the diagnosis is challenging. We aimed to present detailed clinical characteristics and diagnoses of NSUEP from a single center and heighten clinicians' understanding of this condition. Prospectively collected databases were used to retrospectively evaluate patients with NSUEP who underwent treatment at the multidisciplinary consultation center for neck, shoulder, and upper extremity pain at the China-Japan Union Hospital of Jilin University between April 2014 and July 2021. We performed descriptive statistics regarding demographic data, symptoms, findings of physical and radiographic examinations, and each patient's diagnosis. Development of NSUEP was primarily observed in individuals aged between 51 and 60 years (n = 157, 35.4%). Patients were most commonly referred for upper extremity pain (n = 306, 68.9%). Patients with upper extremity pain presented with hypoesthesia (n = 139, 45.4%), muscle weakness (n = 93, 30.4%), muscle atrophy (n = 90, 29.4%), hyperesthesia (n = 39, 12.7%), and turgidity (n = 18, 5.9%). Among the 22 patients with upper extremity swelling, 8 (36.4%) were diagnosed with autoimmune rheumatic diseases. Among the 352 patients with a single diagnosis, 51 (14.5%) presented with thoracic outlet syndrome, 49 (13.9%) with cervical radiculopathy, 16 (4.5%) with carpal tunnel syndrome, and 16 (4.5%) with brachial plexus injury. Further, among the 92 patients with compound diagnosis, 18 patients (19.6%) were diagnosed with cervical radiculopathy. Among the NSUEP patients in this study, older individuals were the largest group. Pain, numbness, weakness, and mobility limitation are common complaints accompanying NSUEP. The common etiologies of NSUEP include cervical spondylosis, thoracic outlet syndrome, carpal tunnel syndrome, and brachial plexus injury. In addition, autoimmune rheumatic diseases should be considered in patients with NSUEP and swelling.