White stuff inside the foreskin may be foreskin scale, or it may be scales or pimples caused by psoriasis, penile pearly papules and other diseases. 1. Foreskin scales: Foreskin scales are caused by factors such as the narrow opening of the foreskin of the penis or the foreskin covering the glans, resulting in the head of the penis not being able to be exposed. If patients do not pay attention to clean it up, it may lead to the accumulation of penile secretions inside the foreskin, which results in the formation of white foreskin scales. 2. Psoriasis: The cause of psoriasis is still unclear, and it is considered to be caused by a variety of factors such as heredity and environment. Patients will have red patches, covered with white scales, localized itching and other symptoms. Psoriasis will also lead to dry skin and rupture and other symptoms. 3. Penile pearly papules: the cause of penile pearly papules is unknown, and it is considered to be caused by physiological variations or local stimulation. The patient’s main symptoms are white papules, pearly and other symptoms, patients with penile pearly papules will also have mild itching and other manifestations. When the patient has the phenomenon of white stuff in the foreskin, it may be the foreskin scale, or it may be caused by other diseases, the patient should consult a doctor in time, and follow the doctor’s instructions for treatment.