Children’s bad breath has different causes, different treatment methods, the main treatment methods are to repair dental caries, pay attention to oral hygiene and so on. 1. Repair caries: if the child has caries, and do not pay attention to oral cleaning, food debris will accumulate in the cavity, it is easy to cause bad breath, this situation requires timely medical treatment, repair caries. 2. Pay attention to oral hygiene: some children do not like to brush their teeth or brush their teeth not thoroughly, the mouth is easy to breed bacteria, bad breath, it is recommended to rinse your mouth after meals, brush your teeth diligently and correctly, in order to maintain fresh breath. As the child’s bad breath may have other reasons, such as indigestion, etc., it is recommended to go to the hospital in time for relevant examinations, clear causes of the disease after active symptomatic treatment.