Background: The impact of preoperative opioid use on outcomes after shoulder surgery is unknown. Purpose/Hypothesis: To examine the role of preoperative opioid use on outcomes in patients after shoulder surgery. We hypothesized that preoperative opioid use in shoulder surgery will result in increased postoperative pain and functional deficits when compared with nonuse. Study Design: Systematic review; Level of evidence, 3. Methods: A systematic review was performed using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Included were all English-language studies comparing clinical outcomes of shoulder surgery in patients who used opioids preoperatively (opioid group) as well as patients who did not (nonopioid group) with a minimum follow-up of 1 year. Outcomes included range of motion, American Shoulder and Elbow Surgeons score, Constant-Murley score, and visual analog scale for pain. Study quality was evaluated with the Modified Coleman Methodology Score and the MINORS score (Methodological Index for Non-randomized Studies). Results: Included were 5 studies (level 2, n = 1; level 3, n = 4): Two studies were on total shoulder arthroplasty, 2 on reverse total shoulder arthroplasty, 1 on both, and 1 on arthroscopic rotator cuff repair. There were 827 patients overall: 290 in the opioid group (age, 63.2 ± 4.0 years [mean ± SD]; follow-up, 38.9 ± 7.5 months) and 537 in the nonopioid group (age, 66.0 ± 4.7 years; follow-up, 39.5 ± 8.1 months). The opioid group demonstrated significantly worse pre- and postoperative visual analog scale and Constant-Murley score pain scores as compared with the nonopioid group. Mean American Shoulder and Elbow Surgeons scores were significantly lower in the opioid group at pre- and postoperative time points as compared with the nonopioid group ( P < .05 for all). However, both groups experienced similar improvement in outcomes pre- to postoperatively. One study showed that the opioid group consumed significantly more opioids postoperatively than the nonopioid group and for a longer duration ( P < .05). The overall mean Modified Coleman Methodology Score and MINORS score were 64.2 ± 14 and 15.8 ± 1.0, respectively. Conclusion: Opioid use prior to various shoulder surgical procedures negatively affected postoperative pain and functionality. Although the opioid group showed significantly worse scores postoperatively, the groups experienced similar improvements.