The paper presents the results of a study of 83 patients with gastroesophageal reflux disease, hypertension and in their comorbidial course. The purpose of the study is to examine the characteristics of heart rate variability (HRV) in the given cohort of patients. Materials and Methods: The main group consisted of 68 patients with a mean age of 35,37 +/- 10,34 years. Patients with isolated pathologies: 20 - with gastroesophageal reflux disease (GERD), 25 - with arterial disease (hypertension) without concomitant diseases. 23 patients had a combination of hypertension and GERD. The comparison group consisted of 15 healthy men. All the subjects were comparable in terms of age, sex, duration of Arterial hypertension and GERD. Results: Patients with associated course of arterial hypertension and GERD were found to have distinctions in HRV parameters, which indicate an increase in sympathetic nervous system activation and a decrease in parasympathetic influence. HRV was non-uniform in patients with different clinical and endoscopic GERD variants. In patients with endoscopically positive GERD (EPRD), there was a significant increase in both time (SDNN, SDANN, SDNN-index), and spectral parameters of HRV (VLF, HF). Conclusion: In associated course of acid dependent diseases (GERD) and hypertension, time and spectral parameters of heart rate variability significantly reduce, reaching the lowest values in patients with signs of reflux esophagitis. Comorbidity of GERD and hypertension exacerbates originally existing excessive influence of the sympathetic nervous system in patients with hypertension, leading to parasympathetic failure, and, ultimately, significantly weakening adaptive capabilities. Revealed changes in HRV parameters among patients with the given sintropy defines such a combination of diseases as undesirable, both for cardiovascular and autonomic nervous systems.