Abstract: [Objective] To evaluate the clinical efficacy of arthroscopic minimally invasive debridement in the treatment of pes anserinus bursitis. [Methods] From October 2015 to October 2018, 12 consecutive patients (21 knees) with pes anserinus bursitis were treated with arthroscopic debridement. There were 5 males and 7 females , aged 31 to 60 years (average 46.5 years). Follow-up assessment included range of motion (ROM), numerical rating scale (NRS) for pain and Lysholm score. [Results] All patients were followed up for 6 to 24 months (average 11.5 months). No serious complications or recurrence occurred postoperatively. The mean preoperative range of motion of the knees improved from (112.50±11.99)° to (134.42±4.23)° at final follow-up (P<0.001). The mean Lysholm score was 57.25±8.31 preoperatively and 85.33±7.11 at final follow-up (P<0.001). The mean NRS pain score during quiet stage was 5.42±1.24 preoperatively and 1.08±0.79 at final follow-up (P<0.001). The mean NRS pain score during movement stage was 6.83±1.34 preoperatively and 1.42±1.17 at final follow-up (P<0.001). [Conclusion] Arthroscopic minimally invasive debridement is an effective and reliable treatment for pes anserinus bursitis leading to knee function recovery and satisfactory clinical outcomes.