Nasal congestion in four-year-old babies can be seen in acute upper respiratory tract infections, rhinitis – sinusitis or other conditions, the intervention needs to be based on different causes, such as general treatment, medication and attention to warmth. 1.acute upper respiratory infection: mostly caused by viruses or bacteria, can be manifested as nasal congestion, light snot, etc., some children can be accompanied by fever, treatment can be used hot towels hot compresses nose, or with wet cotton balls to clean up the nasal passages, but also in the doctor’s guidance using physiological saline for local nasal spray and so on to relieve the symptoms of nasal congestion. 2. Rhinitis – sinusitis: often manifested as nasal congestion, open-mouth breathing, or sleep snoring at night, may be accompanied by pus flow, or sticky white secretion, severe hearing loss can occur. It should be evaluated by a doctor and treated with antimicrobial drugs (e.g. amoxicillin clavulanate potassium, etc.) for anti-infection, or nasal glucocorticoid (e.g. mometasone furoate nasal spray) and nasal irrigation, etc. It is recommended to follow the doctor’s instructions for a full course of standardized treatment. 3. Others: If the ambient temperature is too low, children may also experience nasal congestion, so they should pay attention to keeping warm and increase clothing appropriately. All of the above drugs should be used under the guidance of a doctor. It is recommended to actively consult a specialist for evaluation and treatment to avoid delay.