The sudden growth of small pimples on the man’s pubic area may be caused by warts, scrotal eczema, and jock itch. 1. Acute warts: Acute warts are caused by HPV invasion of the body, immune system disorders, unsafe sex and other factors may also trigger the disease. The patient’s skin will appear skin color or reddish-brown wart-like papules, the most common parts of the external genitalia and perianal skin and other places. 2. Scrotal eczema: the cause of this disease is not yet clear, may be abnormal immune function, genetic and mental factors. The patient’s skin will appear itching, papules and papules, small blisters and other symptoms. 3. Ringworm: ringworm is mainly caused by dermatophyte infections, including Trichophyton rubrum, Trichophyton mustelii, and Trichophyton verrucosum. The disease occurs in the groin area, may also involve the scrotum, penis foreskin and other places, the skin manifested as red spots, pimples and other symptoms. The causes of men’s pubic area suddenly grow small pimples are more reasons, it is recommended that patients go to the regular hospital, relevant examination, clear causes.