Chronic pelvic pain (CPP) affects approximately 26% of women and significantly impacts quality of life. Common causes include dysmenorrhea and pelvic floor dysfunction. Transcutaneous electrical nerve stimulation (TENS) is widely used for pain relief to inhibit pain transmission and stimulate endogenous opioid release. The aim of this study is to evaluate the effectiveness of TENS in the rehabilitation of pelvic pain in women through randomised controlled trials (RCTs). A systematic search was conducted in PubMed and ClinicalTrials.gov databases using the terms “transcutaneous electrical nerve stimulation”, “pelvic pain”, and “pelvic floor”, selecting RCTs published between 2020 and 2025. Inclusion criteria followed the PICO framework, targeting adult women with CPP and TENS as the intervention. Studies involving males, pregnancy, or without full texts were excluded. PRISMA guidelines were followed; study quality was assessed using the Cochrane risk of bias tool. Four RCTs met the inclusion criteria; they involved 281 participants. Three studies focused on primary dysmenorrhea (PD) and one on vestibulodynia. All studies reported a significant reduction in pain following TENS treatment, assessed by the visual analogue scale or numeric rating scale, with some studies also noting reduced analgesic consumption. However, improvements in secondary outcomes such as sexual function and pelvic floor muscle strength were inconsistent. Transcutaneous electrical nerve stimulation appears to be an effective, safe, and non-invasive modality for reducing pelvic pain in women, especially in cases of PD and vestibulodynia. Evidence remains limited by heterogeneity in study protocols and outcome measures. Further high-quality RCTs are needed for standardized protocols and broader rehabilitative outcomes, including functional and quality-of-life improvements.