Study aim: The effect of dry needling on pain and central sensitization (including the Central Sensitization Inventory, electroencephalography, conditional pain modulation, salivary cortisol concentration, and psychosocial variables (7-item general anxiety disorder scale, pain catastrophizing scale, and SF-36 questionnaire) in women with chronic pelvic pain. Design: Single-blind randomized, parallel-group controlled clinical trial, on 36 patients. Randomization will be performed using a computerized Internet-based central randomization service (www.sealedenvelope.com). Assignments and allocation concealment will be sealed in sequentially numbered opaque envelopes by a person who had no direct role in the study. Settings and conduct: Women will be recruited based on the definition of CPP and recognition by an expert in female pelvic floor physicians. All assessments and interventions will conduct in the Research Center of the Faculty of Rehabilitation Sciences of Shiraz University of Medical Sciences. Participants/Inclusion and exclusion criteria: 1. Non-pregnant women in an age range of 20-50 years who are not menopausal, and feel recurrent or constant pain in the pelvis, perineum, anterior abdominal wall below the umbilicus, or in the lower back, pelvic pain unrelated to menstruation, intercourse, or pregnancy lasting for at least 6months. 2. Presence of tenderness/pain when touched in at least one pelvic floor muscle including the levator ani , obturator internus, piriformis, rectus abdominis and external obliqus muscles, and gluteal muscles 3. Score 40-59 in CSI questionnaire (moderate to severe central sensitization level) Intervention groups: dry needling group (DNG), placebo needling group (PNG), control group (CG) Main outcome variables: -short-form McGill pain questionnaire -Central Sensitization Inventory -electroencephalography -conditional pain modulation -salivary cortisol concentration