Background We undertook this study to test the possible correlation between serum concentration of total and specific IgE antibodies and asthma severity in asthmatic children sensitized to the house dust mite Dermatophagoides pteronyssinus. Methods The study included 157 asthmatic children aged 5–15 years (8 ± 3 years). Clinical diagnosis was based on personal and family history, physical examination, pulmonary function testing and skin tests. Asthma severity was determined according to GINA guidelines. In vitro tests included serum concentration of total and specific IgE. Results All asthmatic children had elevated serum concentration of total IgE. The children with elevated serum concentration of total IgE also showed an increased serum concentration of specific IgE. Asthma of higher higher severity was present in patients with total IgE concentration >288.0 kIU/L (AUC = 0.736) and specific IgE to Dermatophagoides pteronyssinus >44.1 kIUA/L (AUC = 0.843). Intermittent asthma was present in 76.9% of children with specific IgE concentration <44.1 kIUA/L. The positive predictive value suggested with 79.2% probability that a child with a concentration of specific IgE to Dermatophagoides pteronyssinus >44.1 kIUA/L would have a more severe form of asthma. Conclusions Asthmatic children with higher asthma severity have a higher serum concentration of both total IgE (>288.0 kIU/L) and specific IgE to Dermatophagoides pteronyssinus (>44.1 kIUA/L), respectively.