Objective To evaluate the efficacy of minimally invasive percutaneous plate osteosynthesis (MIPPO) in the treatment of Neer three-part fractures of the proximal humerus in young adults. Methods A retrospective analysis was performed of the 46 patients aged < 65 years with Neer three-part fracture of the proximal humerus from March 2010 to December 2016. MIPPO with locking proximal humerus plate ( LPHP ) was used in 23 of them who were 12 men and 11 women with an average age of 41. 6 ± 1. 2 years; open reduction and internal fixation ( ORIF ) with LPHP was used in the other 23 patients who were 14 men and 9 women with an average age of 42. 2 ± 1. 6 years. The 2 groups were compared in terms of operation time, intraoperative bleed-ing, fracture healing time and shoulder function by Neer scoring at the last follow-up. Results The average follow-up ( 13. 4 ± 1. 2 months ) for the MIPPO groups was not statistically different from that for the ORIF group ( 14. 2 ± 2. 4 months ) ( P > 0. 05 ) . The MIPPO group reported significantly shorter operation time ( 105 ± 15 min ) , significantly less intraoperative bleeding ( 140 ± 50 mL ) , significantly shorter fracture healing time ( 4. 2 ± 0. 6 months ) , and significantly higher shoulder Neer scores ( 88. 6 ± 3. 4 ) than the ORIF group ( 120 ± 20 min, 320 ± 40 mL, 5. 4 ± 1. 2 months, and 81. 6 ± 2. 2, respectively ) ( P <0. 05 ) . The complication rate ( 4. 3％, 1/23 ) for the MIPPO group was not significantly different from that for the ORIF group ( 17. 4％, 4/23 ) ( P >0. 05 ) . Conclusion MIPPO with LPHP may be obviously advantageous over ORIF with LPHP in the treatment of proximal humeral fractures in young adults.