Red bumps on a child’s face like an allergy can be caused by contact dermatitis, eczema, chicken pox and other causes. 1. Contact dermatitis: If a child’s face comes into contact with allergenic substances, it can cause the body’s immune response, and red bumps can appear. 2. Eczema: If a child has eczema on the face, the skin may appear pinhead to corn size pimples, which may look like allergies. 3. Chickenpox: When a child is infected by chickenpox virus, red papules, herpes and scabs may appear on the face. Parents are advised to take their children to regular hospitals in time to clarify the cause of the disease and standardize the treatment under the guidance of the doctor, so as not to delay the disease to bring adverse effects on the body.