A therapeutic complex based on pelotherapy given as mud applications or electrophoresis of squeezed mud on the area of lung root projection (a total of 10-12 procedures, each other day) was tested in 99 patients with chronic bronchitis (CB). 68 CB controls received the above complex but no peloids. The results were assessed by clinical changes, clinical biochemical indices, immunograms, changes in external respiration function. The pelotherapy was found to have a corrective effect on CB pathogenesis and a stimulating action on sanogenic mechanisms of the body.