The review is dedicated to the analysis of ecological aspects of pollen allergy (pollinosis). The characteristic of pollen as a natural aerosol component is given. The information related to aeropalinological monitoring and its importance in public health service is presented. The peculiarity of this pathology is its regional variety associated with differences in plant species compositions and pollen periods. The problem of immune response formation to pollen has been studied most profoundly. At that it is known that sensibilization is not always associated with clinical signs. Russian and foreign data about correlation studies between the pollen quantity and the disorder symptom load are discussed. It is shown that there is no decisive answer to the question about threshold pollen counts of certain plants and its impact on different stages of respiratory diseases. The detailed analysis of the correlation between the symptoms and quantitative variables of pollen allergens may provide useful information for risks evaluation of disease exacerbation as well as for tactics elaboration of hypoallergic measures. This is a cross-disciplinary issue involving allergology, aerobiology and ecology. The perspective of further development of this subject in order to obtain more accurate vision of the reasons, mechanisms and patterns of all parts of multifactorial process of pollinosis formation is discussed.