Allergic rhinitis (AR) is a common immunoglobulin E (IgE) dependent disease among allergic patients worldwide. At the same time, the determination of specific IgE in the blood serum allows characterizing the relevant sensitizing allergens. Despite the existence of conditional thresholds for normal and elevated levels of total and specific IgE, there is no consensus in the literature on which IgE value unequivocally confirms the presence of atopy and what is the relationship between these levels and the severity of clinical manifestations. Purpose - to evaluate the levels of serum total and specific IgE and their relationship with severity and age in children with persistent AR and combined with bronchial asthma (BA) during sensitization to house dust mite (HDM) allergens. Materials and methods. A clinical, anamnestic and laboratory examination of 259 children aged 5 to 17 years with AR and combined AR with BA, who were sensitized to HDM allergens, was conducted. Results. In AR in children with sensitization to HDM, there is a dependence of serum total IgE level on the severity of AR and age of children. With increasing severity of AR manifestations, a significant (p<0.05) increase in total IgE levels was noted. It was found that the content of sIgE also increased with increasing severity of AR. Thus, statistically significantly (p<0.05) higher levels of sIgE were determined in sensitization to the major HDM molecules Der f 1, Der p 1, Der p 2, Der p 23 in children with severe AR. Sensitization to the tropomyosin Der p10 molecule, which usually has no effect on the clinical manifestations of respiratory allergy but indicates cross-reactivity to seafood, was significantly more common (p<0.05) in children aged 3-7 years compared to children aged 13-17 years. Conclusions. The data obtained partially define the pathogenetic features in the formation of sensitization to HDM and their individual molecules, confirming that this process begins at an early age, which may indicate the need to start allergen-specific immunotherapy in such children if clinically necessary. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of the participating institution. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.