Nerve growth factor, a kind of neurotrophic factor, plays an important role in neuronal development, differentiation, survival and neurogenesis, and is considered as a link between neuroendocrine system and immune system in asthma attack. The possible mechanism of effects of nerve growth factor on asthma is as follows: (1) nerve growth factor changes airway innervation, and facilitates the synthesis and release of neurotransmitter in nerve terminal, which will contribute to airway remodeling; (2) nerve growth factor induces eosinophils aggregation, proliferation and releasing inflammatory factor, which will lead to the abnormality of immunologic response; (3) nerve growth factor triggers the redundancy of adrenal medullary cells, which results in adrenal medullary cell to nerve cell transition, and then the impairment of chromaffin cell endocrine secretion function. As a result, the concentrations of adrenaline in circulation are not competent to relieve the bronchoconstriction in asthmatic attack.