Technical complexity and highly traumatic character of selective proximal vagotomy in all its modifications are considered to be the main causes of the postvagotomy complications. Experimental investigations in 38 mongrel dogs allowed the authors to develop and introduce into practice a new method of seromuscular proximal vagotomy with using radio waves. The selective destructive effect of the radio waves on the nerve tissues, evidenced by morphological investigations was taken into consideration and allowed the destruction of the vagus nerve branches in deep layers of the gastric wall to be performed. This method of vagotomy was used in 46 patients with ulcer disease of the duodenum and gave good results. When studying the functional state of the stomach and duodenum the authors widely used their modification of rheography of the gastric blood flow controlled by fibrogastroduodenoscopy in addition to routine methods of the functional diagnostics.