Nowadays, control of bronchial asthma (BA) can be achieved only in 2/3 of cases, even in a controlled population with direct daily supervision of a doctor ensuring full compliance with standard treatment regimens. In this regard, factors that can affect the course of asthma, but those which are not taken into account in standard treatment regimens, are of particular importance. Interest in vitamin D as a modifier of atopic inflammation in BA is due to its noncalcemic effects realized through the VDR receptors of immune cells. 78 patients suffering from asthma were examined. The diagnosis of the disease and the degree of control over it were established based on the GINA 2020 criteria. The levels of vitamin D and interleukins in the blood serum were determined by ELISA. The level of immunocompetent cells was determined by flow cytometry. The presence of persistent infection was determined by PCR method. It was found that children with uncontrolled AD have more than two times (29.8 vs 64.5 ng/ml) lower level of vitamin D than patients who control the disease. Children with vitamin D deficiency have three times higher levels of one of the inducers of atopic inflammation – IL5 (0.62 vs 0.22 pg/ml) and require a higher dose of topical glucocorticosteroids (TGC) (347.3 vs 285.5 mcg) to control the disease. Thus, vitamin D has a significant impact on the level of asthma control in children, the immune status and the likelihood of persistence of the herpes virus type 6. Determination and correction of vitamin D deficiency should be recommended, since it influences on pathogenetically significant parameters of atopic inflammation in uncontrolled bronchial asthma in children.