Infants always sneeze, which may be caused by physiological or pathological factors. Physiological factors such as air irritation; pathological factors such as allergic rhinitis and acute upper respiratory tract infections can cause infants to sneeze. 1. Physiological factors: when there are irritating odors, too cold or too hot gases in the environment, it is easy to stimulate the infant’s nasal mucosa and cause sneezing, which is a physiological defense measure. 2. Pathological factors: when infants suffer from allergic rhinitis, they will sneeze continuously and violently after being stimulated by allergens such as pollen, animal hair and irritating gases; in addition, acute upper respiratory tract infections, including common colds, can also cause prolonged sneezing in infants. There may be other reasons for infants to sneeze all the time. It is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, and then give targeted treatment or therapy under the guidance of the doctor.