Generally children with low androgen tend to have the following clinical symptoms. First, the reduction of axillary and pubic hair, because the growth of children’s axillary and pubic hair is mainly under the action of androgen, especially at puberty, children begin to have axillary and pubic hair production. If there is too little androgen, the growth of armpit and pubic hair tends to be more backward or sparse. Secondly, the voice is sharp, because after androgen production, children will change their voice, especially for boys. Children with low androgen will be impaired in voice change, and after puberty the voice is still similar to the child’s voice, so if children have low androgen, they should be treated with testosterone in a timely manner.