Allergy to house dust mites is the main cause of respiratory forms of allergy, namely allergic rhinitis and asthma. 1–2% of the world’s population is sensitized to house dust mites, which is equivalent to 65–135 million people. In general, the existence of more than 150 species of house dust mites has been proven today. Among them, the most common and clinically significant species are Dermatophagoides pteronyssinus and Dermatophagoides farinae. The article presents practical advices on recognition, diagnosis, treatment of allergy to house dust mites and prevention of symptoms of the disease.