Age, minimum joint-space, and the presence of acetabular subchondral cysts are statistically significant risk factors for failure of hip arthroscopy. Gender, center edge angle, and size of subchondral cysts are not reliable predictors of failure. The purpose of this study was to identify pre-operative predictors of early failure following hip arthroscopy. From 2006-2009, a single surgeon consecutive case series of 263 hip arthroscopies was retrospectively reviewed. Two cohorts of subjects were evaluated; failures of hip arthroscopy and those who have not undergone any further operative intervention of the involved hip since arthroscopy, with a minimum 2-year follow-up. Failure was defined as patients who have undergone a total hip arthroplasty within 2 years of arthroscopy . A total of 68 successful patients, with a minimum 2-year follow-up, and 23 patients who failed hip arthroscopy met inclusion criteria, for a total of 91 patients. Pre-operative radiographs were measured for minimum joint-space width and center-edge angle. Pre-operative MRIs were reviewed by one MSK radiologist who was blinded to arthroscopic findings and patient outcomes. Variables studied inclded gender, age, minimum joint-space, center-edge angle, presence/absence of acetabular subchondral cysts, and size of cysts. Exclusion criteria included any patient whose pre-operative radiographs and/or MRI were not available for review. Patients in the successful cohort were attempted to be contacted via telephone to confirm that no additional surgery was performed to the involved hip since the last follow-up visit. Of the 91 patients, 43 had available for review both pre-operative radiographs and MRs. Twenty-seven patients were classified as successful (9 male, 18 female) and 16 patients (5 male, 11 female)failed hip arthroscopy. The difference in gender was not found to be statistically significant (p=0.56). Average age of the successful cohort was 45.15 years and 51.38 years for the failure cohort. This difference is statistically significant (p=0.04). Average minimum joint-space for the successful cohort was 3.93 mm and 2.63 mm for the failure cohort. This difference is statistically significant (p=0.049). Average center-edge anle for the successful cohort is 37.8° and 32.5° for the failure cohort. This difference is not statistically significant (p=0.06). Of the 27 patients who were classified as being successful, 3 had acetabular subchondral cysts. Of the 16 failures, 12 had acetabular subchondral cysts. This difference is statistically significant (p=0.0001). Ten cysts measured < 1cm, whereas 5 cysts measured > 1 cm. Of the 10 small cysts, 2 patients succeeded and 8 patients failed. Of the 5 larger cysts, 1 patient succeeded and 4 patients failed. This difference is not statistically significant (p=0.5). Of the 27 successful patients, 24 were reached via telephone (89%) and confirmed that no additional surgery had been performed on the involved hip since the last follow-up visit. Age, minimum joint-space, and the presence of acetabular subchondral cysts are statistically significant risk factors for failure of hip arthroscopy. Gender, CEA, and size of subchondral cysts are not reliable predictors of failure. Current recommendations on hip arthroscopy suggest that a minimum joint-space of 2 mm is appropriate for proceeding. However, our findings suggest that the presence of acetabular subchondral cysts is a more sensitive predictor of failure following hip arthroscopy than minimum joint-space.