Background: Hip arthroscopy is now commonly used to treat hip pain and pathology, including osteoarthritis (OA). Despite this, little is known about the effect of hip arthroscopy on outcomes of pain and function and progression to total hip arthroplasty (THA) in hip OA. Questions/purposes: This systematic review aimed to (1) determine pain and function outcomes after hip arthroscopy in people with hip OA; (2) compare the outcome after hip arthroscopy between people with and without hip OA; and (3) report the likelihood of progression to THA in patients with hip OA after hip arthroscopy. Methods: This review was conducted in accordance with the PRISMA statement. The Downs and Black checklist was used for quality appraisal. Studies scoring positively on at least 50% of items were included in final analyses. Standardized mean differences (SMDs) were calculated where possible or study conclusions are presented. Results: Twenty-two studies were included in the final analyses. Methodological quality and followup time varied widely. Moderate to large SMDs were reported for people with and without hip OA; however, the positive effects of the intervention were smaller for people with hip OA. Greater severity of hip OA and older age each predicted more rapid progression to THA. Conclusions: Patients with hip OA report positive outcomes from hip arthroscopy, although observed positive effects may be inflated as a result of methodological limitations of the included studies. Patients with hip OA had inferior results compared with those who did not. Chondropathy severity and patient age were associated with a higher risk and more rapid progression to THA. High-quality comparative studies are required to confirm the effects of hip arthroscopy on symptoms and structural change in people with hip OA.