Background: Characteristics regarding mechanism of injury, management, and return-to-play (RTP) rate and timing are important when treating and counseling athletes with rectus femoris tears. Purpose: To systematically review the literature to better understand the prevalence, sporting activity, injury mechanisms, and treatment of patients with rectus femoris injury and to provide prognostic information regarding the rate and timing of RTP. Study Design: Systematic review; Level of evidence, 4. Methods: Following the 2020 PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, we queried PubMed/MEDLINE, Cochrane, OVID, EMBASE, and Google Scholar in March 2022 for studies reporting on athletes sustaining isolated, full-thickness tearing, or bony avulsion injuries to the proximal rectus femoris during sporting activity. Excluded were studies without evidence of full-thickness tearing or avulsion, with athletes sustaining concomitant injuries, or with injuries occurring from nonsporting activities. The percentage of athletes sustaining injuries was calculated based on sport, injury mechanism, and management (nonoperative versus operative). Results: Of 132 studies initially identified, 18 were included, comprising 132 athletes (mean age, 24.0 ± 5.4 years; range, 12-43 years). The most common sporting activities were soccer (70.5%) and rugby (15.2%). The most reported mechanisms of injury were kicking (47.6%) and excessive knee flexion/forced hip extension (42.9%). Avulsion injuries were reported in 86% (n = 114) of athletes. Nonoperative management was reported in 19.7% of athletes, with operative management performed in 80.3%. The mean follow-up time was 21.4 ± 11.4 months (range, 1.5-48 months). The RTP rate was 93.3% (n = 14) in nonoperatively treated and 100% (n = 106) in operatively treated athletes, and the mean RTP time was 11.7 weeks (range, 5.5-15.2 weeks) in nonoperatively treated and 22.1 weeks (range, 14.0-37.6 weeks) in operatively treated athletes. Complications were reported in 7.7% (2/26) of nonoperatively treated and 18% (n = 19/106) of operatively treated athletes. Conclusion: Full-thickness proximal rectus femoris injuries occurred most frequently in athletes participating in soccer and rugby secondary to explosive, eccentric contractions involved in kicking and sprinting. Operative management was performed in the majority of cases. Athletes who underwent operative repair had a 100% RTP rate versus 93.3% in athletes treated nonoperatively.