White tofu scum on the genitals of a 6-year-old boy may be caused by mycosis genitalis, foreskin scaling, sebaceous gland ectasia and other causes. 1. Penile inflammation: the causes include infectious factors such as bacterial, fungal and viral infections, and non-infectious factors such as alkaline stimulation and friction. It is often characterized by redness and swelling of the genitals, pain, frequent urination, painful urination, and purulent discharge from the head of the penis. 2. Circumcision: If the foreskin is not cleaned properly, the sebaceous gland secretion residue is easy to generate circumcision, and may also appear white tofu slag-like. 3. sebaceous gland ectopic: sebaceous glands in the growth and development of sebaceous gland secretions block pores, local sebaceous gland ectopic, which leads to white particles in the genital area. Boys with white tofu scum-like discharge from the genitals should seek timely medical attention and standardized treatment under the guidance of a doctor.