Abstract: Objective  To investigate the prevalence of Dermatophagoides pteronyssinus in children allergic diseases in Hangzhou and its surrounding areas.  Methods   Western blotting was used to detect the serum antibody for 9 422 children who were admitted due to clinically suspected allergic diseases. Clinical epidemiological features were analyzed for those with total IgE>100 IU/ml and Dermatophagoides pteronyssinus-specific IgE≥0.35 IU/ml.   Results   The prevalence of Dermatophagoides pteronyssinus in children with allergic diseases was 41.2%（3 878/9 422）. The most common symptoms were allergic rhinitis ［47.8%（1 852/3 878）］ and asthma［18.5%（716/3 878）］. The allergic diseases were most prevalent in July, August and October. The diseases were more prevalent in children over 3 years old and above. more in males ［68.8%（2 668/3 878）］ than females［31.2%（1 210/3 878）］.   Conclusion   Data suggest that Dermatophagoldes pteronssinus is an important allergen causing allergic diseases in children in Hangzhou.

Key words: Dermatophagoides pteronyssinus, Specific IgE, Children