The nose is one of the organs of the human respiratory system and should not generally smell bad. Once you find that your child’s nostrils emit a fishy smell, you should immediately look for the cause and treat it in a timely manner, do not be careless. There are many causes of nasal odor in children, and one of the more common is a foreign body in the nasal cavity. Children often like to stuff some small things into the nasal cavity, but due to their own lack of ability to remove, digging with their fingers instead of pushing it deep into the nasal cavity. From time to time, the foreign body stored in the nasal cavity stimulates the nasal mucosa, causing congestion, swelling, increased nasal discharge, resulting in infection and inflammation, plus the nasal secretions constantly adhering to the surface of the foreign body, causing nasal blockage, resulting in the flow of pus and blood-like nasal discharge from time to time, and emitting a burst of fishy odor. In addition, children’s nasal septum is infected with abscesses, and when it breaks down, there is also pus and blood-like nasal discharge and a fishy odor. In maxillary sinus osteomyelitis, when the mucous membrane of the nasal cavity is penetrated, foul-smelling pus and blood-like nasal discharge also occurs in the nose. The fishy odor emitted by some extra-nasal diseases can sometimes be exhaled from the nose due to the adjacent nasal cavity, such as purulent tonsillitis, gum abscess secondary infection, dental caries, lung inflammation abscess, etc. When nasal odor occurs in children, the symptoms can be eliminated as long as the specific cause is addressed. If the foreign body in the child’s nose is removed, the nasal odor will soon disappear; timely control of nasal septal abscess and maxillary sinus osteomyelitis, pay attention to the treatment of diseases in the adjacent parts of the nasal cavity, the same can also make the nasal odor lifted.