The causes of children’s thick tongue include the following: First, the symptoms caused by children suffering from accumulation of food. Because children’s spleen and stomach are weak in transporting and transforming, a little too much food or improper diet will cause indigestion. When children suffer from indigestion, they will have a thick and greasy tongue and often have a sour taste in their mouth and sour and foul-smelling stools. In this case, the child can be given timely treatment to eliminate food and lead to stagnation, which can be applied to Bao He Wan. Secondly, children with respiratory tract infections may suffer from symptoms. If the child has a phlegm-heat cough or a phlegm-damp cough, the child will also have a thick and greasy tongue coating and needs to be treated promptly to resolve the phlegm.