As sports have increased in popularity, the incidence of tendinopathy has also grown dramatically. Nonoperative techniques and treatments used to address these pathologies continue to evolve and improve. One such treatment, prolotherapy (PrT), has become increasingly popular and may provide patients with an alternative nonoperative treatment option. To review high-quality randomized controlled trials (RCTs) that analyzed PrT treatments for the most common tendinopathies. Specifically, this review aims to provide meaningful data regarding methods and outcomes for each condition treated and guide professionals who are considering PrT as a treatment option. Systematic review; Level of evidence, 2. All RCTs published in English between January 1, 1980, and July 30, 2021, and reported in Embase, Medline, and Web of Science databases were reviewed according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. After the initial search, a total of 3264 articles were identified. Studies analyzing sports medicine injuries and musculoskeletal pathologies using an RCT design were included, while case-reports, case-studies, reviews, and observational studies were excluded. Two independent researchers reviewed the search results, and conflicts were resolved by discussion of inclusion and exclusion criteria among all authors. The articles' quality was evaluated using the Cochrane tool for assessing the risk of bias. Statistical analysis and graphical representations were performed using SPSS Version 28.00. A total of 20 articles, including 1136 patients, met the inclusion criteria and were included in the study. Overall, in 85% of the studies, PrT was found to be effective in the treatment of tendinopathy. Specifically, PrT was superior to or as effective as the control in 83% (10/12) of the studies analyzing lateral epicondylitis (LE) and rotator cuff (RC) tendinopathies and in 88% (7/8) of the studies on plantar fasciitis (PF), Osgood-Schlatter disease (OSD), and Achilles tendinosis (AT). LE, RC, and PF tendinopathies were the most studied conditions (17/20 studies), while AT and OSD were the least studied (3/20 studies). Of the studies, 95% (19/20) used dextrose solutions, with only 1 using solutions of 2.5% phenol, 25% glycerin, and 25% dextrose in sterile water. Our systematic review suggests that PrT appears to be a promising alternative treatment for common tendinopathies. Most studies used a hypertonic dextrose solution. Even though further, larger randomized controlled trials comparing PrT with other orthobiologics would be beneficial, based on this review, sports medicine physiciansmay safely pursue PrT as an additional component of conservative treatment.