Ecological and physiological studies conducted in recent years show that one of the most important factors determining the state of health is the environment. Natural and climatic factors of the Arctic zone contribute to a decrease in the reserve capacity of human immune homeostasis, the reduction of which forms secondary environmentally dependent immune imbalances, manifested by chronic pathology and frequent recurrences of diseases in the anamnesis, in particular, erosive gastritis. The study of the adaptive immune response during the period of long-term remission is extremely important, it allows us to predict the recurrence of the disease and carry out timely prevention. The study involved 30 women, aged 50–70 years with a history of chronic gastritis in the stage of long-term remission (3–5 years), residents of the Arctic region of the village. Pinega Arkhangelsk region. The study of the immune status included the determination in the peripheral blood of: the content of lymphocytes with CD3⁺, CD5⁺, CD8⁺, CD16⁺, CD25⁺, CD95⁺ receptors; phagocytic activity, phagocytic number using the application package Statistica 10.0, Microsoft Excel 2010. It was found that elevated concentrations of natural killer cells (CD16⁺) and cytotoxic cells (CD8⁺) occurred in 28,57±1,77% and 60,00±2,56% of cases, respectively, against the background of a pronounced deficiency in the content of T-lymphocytes (CD5⁺) in 96,66±3,26% and (CD3⁺) in 96,29±3,25% of the subjects, which indicates a reduction in the reserve capacity of immune homeostasis. Deficiency of phagocytic activity was registered in 23,33±1,60% of individuals. The revealed increased concentrations of cells with CD25⁺ and CD95⁺ receptors, combined with a high activity of phagocytosis, in our opinion, should be considered a compensatory mechanism of the adaptive immune response with a favorable prognosis for maintaining a long-term remission of the disease.