The most common cases of hair loss in children are mainly due to baldness, and most of them are due to the lack of trace elements, as follows: 1. Calcium deficiency: children with calcium deficiency sometimes experience hair loss in the early stages, mainly occipital baldness; 2. Fungal infection: the most common cause of hair loss in children is fungal infection of the scalp area, namely ringworm, which causes round patches of hair loss on the scalp, with local skin turning pink or gray. There is flaking and intense itching; 3, mental involuntary movements or behavioral disorders: such as rubbing, rubbing, pulling the scalp and causing hair loss; 4, disease factors: such as hypothyroidism and hypopituitarism, can also lead to hair loss in various parts of the child’s head.