The pus inside the penile skin like pimples may be caused by boils, genital herpes, sebaceous cysts combined with infections and so on. 1. Boils: If the follicles of the penis are infected by bacteria such as staphylococcus, it can cause pus to appear locally. 2. Genital herpes: In acute attacks, multiple blisters can be seen on the genitals, which may be accompanied by pustules. 3. Sebaceous cysts combined with infection: If sebaceous cysts are combined with staphylococcus and other pus-filled bacterial infections, the phenomenon of pimples with pus in them can also occur. It is recommended to go to the hospital in time for pus inside the penis skin like pimples, to clarify the cause of the disease, and to standardize the treatment under the guidance of the doctor.