Prolotherapy, a nonsurgical regenerative injection therapy, is becoming increasingly popular among the pain physicians as well as patients. The current theory suggests that the prolotherapy mimics the natural healing process of the body by initiating a local inflammatory cascade, which triggers the release of growth factors and collagen deposition. Although the clinical literature on prolotherapy had been published since last 80 years, the quality, number, and research have increased since the 1990s. The growing body of evidences suggests its use in osteoarthritis, low back pain, and tendinopathies. With recent advances in stem cell therapy and regenerative medicine, prolotherapy will play a greater role in the treatment of chronic degenerative conditions and sports injuries.