There are many causes of supragenital fissures, such as trauma, prepuce, infectious factors, allergic causes, eczema and so on. 1. Trauma: For example, the genitals are squeezed by external forces, bumps, bruises and wrong way of sexual intercourse, which may lead to genital fissures. 2. Circumcision: congenital developmental factors cause the opening of the foreskin to be narrow and tightly encircled around the glans, preventing the glans from being exposed, which may lead to rupture of the foreskin due to penile erection. 3. Infectious factors: for example, bacterial, viral, trichomonas, fungal, mycoplasma infections, may also cause symptoms of cracks on the genitals. 4. Allergic causes: for example, contact dermatitis, drug rash and other allergic factors may also cause cracks on the genital skin. 5. Eczema: Inflammatory skin reactions caused by internal and external stimuli, chronic eczema may also cause genital skin roughness, cracks and other symptoms. To summarize, there are many causes of cracks on the genitals, you should go to the hospital in a timely manner, to clarify the cause of the disease and follow the doctor’s instructions for treatment.