Bronchitis in babies can complicate into bronchopneumonia if not treated promptly. The ends of the right and left bronchial tubes of the human body carry the lungs through the hilum. Bronchitis in babies is mostly caused by viral or bacterial infections, pathogenic microorganisms are concentrated in the bronchial area causing inflammatory reaction of the bronchial mucosa, but if the treatment is not timely or poorly treated, the bacteria or viruses may travel down to the lungs, thus causing bronchopneumonia. Therefore, when babies develop symptoms such as cough, sputum, fever, wheezing, etc., parents should be vigilant and bring their children to the hospital in a timely manner. Babies who have been diagnosed with bronchitis need to be treated as early as possible under the guidance of a doctor, as delayed treatment may cause complications such as bronchopneumonia and bronchial asthma.