Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) is a common disorder in adult men. Evidence has demonstrated that acupuncture is effective for treating CP/CPPS. Electroacupuncture (EA) is a combination of traditional acupuncture and electrical stimulation, and the waveform is one of the key factors influencing EA effects. Different waveforms contain different stimulating parameters, thus generating different effects. However, the effects of different waveforms of EA on CP/CPPS remain unclear and there is no recommended standard for the application of EA waveforms. At the same time, the waveform prescription of CP/CPPS is also different, so exploring the influence of different waveforms on CP/CPPS patients will also provide a certain treatment basis for clinical treatment. A total of 108 eligible patients were recruited from the Seventh People's Hospital affiliated to the Shanghai University of Traditional Chinese Medicine from March 18, 2021, to January 31, 2022, according to inclusion and exclusion criteria. All subjects were randomly divided into three groups (continuous wave 4 Hz, continuous wave 20 Hz, and extended wave 4/20 Hz) in a ratio of 1 : 1 : 1. Patients in all three groups were treated for the same duration of 20 minutes, with intervention twice a week for 4 weeks. The changes in chronic prostatitis index (NIH-CPSI), erectile function index 5 (IIEF-5), Hospital Anxiety and Depression Scale (HADS), and NIH-CPSI response rate in three groups were compared after the intervention, and the occurrence of adverse events in patients during treatment was observed. After 4 weeks of treatment, the CP/CPPS response rates were 66.7%, 62.5%, and 88.2% in the 4 Hz, 20 Hz, and 4/20 Hz groups, respectively. The reaction rate of CP / CPPS in 4 / 20 Hz group was higher than that in 4 Hz group and 20 Hz group. ( P < 0.05). During treatment, the difference between NIH-CPSI scores between 4 Hz and 4/20 Hz was insignificant ( P > 0.05). NIH-CPSI scores were lower in the 4/20 Hz group than in the 4 Hz and 20 Hz groups ( P < 0.05). After treatment, there was no significant difference in the pain and discomfort subscales ( P > 0.05) between the 4 Hz and 20 Hz groups and there were significantly lower pain and discomfort scores in the 4/20 Hz group ( P < 0.05) compared to the 4 Hz and 20 Hz groups. There was no significant difference in the reduction of urination symptoms and quality of life among the three groups ( P > 0.05). Compared with before treatment, IIEF-5 scores of the three groups were improved ( P < 0.05). After treatment, there was no significant difference between the IIEF-5 scores in 4 Hz and 20 Hz ( P > 0.05), while the IIEF-5 score in 4/20 Hz was significantly higher than that in 4 Hz and 20 Hz, and the change was significant ( P < 0.05). The HADS scores decreased in all the three groups ( P < 0.05), but there was no significant difference in HADS scores between the three groups ( P > 0.05). Adverse events were mild and transient, and no serious adverse events occurred in each group. Both the expansive and continuous waveforms of EA can effectively alleviate symptoms such as prostatitis, erectile dysfunction, anxiety, and depression in patients with CP/CPPS. Expansion waves are superior to continuous waves in improving erectile function and pain symptoms in chronic prostatitis and can be used as a preferred waveform for the treatment of CP/CPPS. Trial Registration. This trial is registered with Chinese Clinical Trial Registry, ChiCTR2100044418 .