The aim of the research is to develop a mathematical model of selection of phenotypes of bronchial asthma (BA) at a resort stage of medical rehabilitation. Materials and methods: 300 patients with BA who arrived at the climatic resort for medical rehabilitation; values of 64 indices of the research describing features of emergence and a course of a disease; the current clinic-functional state of patients; the discriminant analysis for the creation of a mathematical model. Results of the research: by the discriminant analysis there were created 7 statistically significant linear discriminant functions for the discernment of BA phenotypes; 23 indices of the research were under study: gender, asthma control, quantity of not allergic associated diseases, coughing during the day, character of the sputum, expressiveness of symptoms of asthma, use of rescue medication, the number of dry rattles in lungs, severity of hypostases, systolic and diastolic arterial blood pressure, shortness of breath, wheezing, reaction to the change of weather, allergic reactions, existence of symptoms of intoxication and feature of treatment of the last exacerbation, a dose of inhaled glucocorticosteroids, presence of emphysema and fibrosis in lungs at the X-ray examination, expressiveness of electrographic changes, FEF25-75%, 6-minute walk test. Conclusion: the procedure of the selection of 7 BA phenotypes at the resort stage of medical rehabilitation can be carried out by the use of the mathematical model consisting of 7 linear discriminant functions including 23 indices; the accuracy of the selection of the offered BA phenotypes of the developed mathematical model in general is 89.0%.