White patches on the back of a child’s stomach may be caused by vitiligo, lichen planus, lack of trace elements and other reasons. 1. Vitiligo: it is mainly manifested by the loss of skin color and whitening of the damaged area, and may occur in any part of the child’s stomach and back. 2. lichen planus: if malassezia invades the skin cuticle of the child’s stomach and back, hypopigmentation and other phenomena can occur. 3. Lack of trace elements: trace elements such as copper and selenium are involved in the synthesis of melanocytes, and the lack of trace elements will affect the synthesis of melanocytes, which may lead to the appearance of white spots on the stomach and back. Parents are advised to bring their children to the hospital in time, to clarify the cause of the disease, and to standardize the treatment under the guidance of the doctor, so as not to delay the condition.