Methods of treating premature ejaculation include arranging one or more electrodes to face dorsal penile nerves (DPNs) of a patient with premature ejaculation, and applying an electro stimulation having a frequency and a current by which seminal fluid expulsion is not induced in the patient by the one or more electrodes during a time period from before the start of sexual intercourse to ejaculation. The electro stimulation reversibly extends an intravaginal ejaculatory latency time (IELT) of the patient. Methods of controlling a premature ejaculation treatment device are also provided.