Aim. To comparatively analyze clinical manifestations in patients with primary esophageal spasm (ES) and its concurrence with gastroesophageal reflux disease (GERD) and the results of their instrumental examinations and psychodiagnostic tests. Subjects and methods. A total of 104 patients with the clinical and manometric signs of ES were examined and divided into two groups: 1) 42 patients with primary ES; 2) 62 patients with ES concurrent with GERD. The examination encompassed esophageal manometry, esophagogastroduodenoscopy, 24-hour pH metry, and an interview using a questionnaire to identify autonomic disorders, and the Mini-Mult test. Results. The patients with primary ES compared to those with ES concurrent with GERD significantly more frequently showed severe pain syndrome (p=0.009) and a paradoxical dysphagia pattern (p=0.03); manometry revealed an incoordination in the motility of the entire esophagus (p=0.001). Comparison of the statistical series of values for contraction amplitude and duration in the distal esophagus found no significant difference in the patients of both groups. Autonomic disturbances were detected in 76.0% of the patients with ES; but the intergroup differences were insignificant. Mental maladaptation was observed in 81.7% of the patients in the absence of intergroup differences. Conclusion. The etiopathogenetic factor of ES is a psychoautonomic response to chronic stress in both primary ES and its concurrence with GERD. The reflux of gastric contents into the esophagus does not appear to be one of the leading causes of ES. In primary ES, esophageal motor function is generally impaired to a much greater extent than that in ES concurrent with GERD. The degree of motor disorders is embodied in the specific clinical features of the disease.