Objective To evaluate the feasibility and clinical outcomes of minimally invasive treatment via anterolateral acromial approach (ALA) for severely impacted valgus fractures of the proximal part of the humerus. Methods From June 2011 to May 2013, a total of 20 patients with severely impacted valgus proximal humeral fracture were treated through ALA in a minimally invasive manner. Direct reduction, bone grafting, reconstruction of the rotator cuff insertion and Proximal Humerus Internal Locking System (PHILOS) planting were well carried out. Systematic rehabilitation exercise of the shoulder joint was performed postoperatively. Results All the patients were followed-up for at least one year, with an average of (15±3) months (range 12~36 months). No axillary neurapraxia occurred that could be attributed to the surgical approach. All fractures healed within 6 months, and the average Constant-Murley score at 1 year was (83.0±1.5) (range 79.0 to 89.5) during a 12-month follow-up. There was no internal fixation failure or avascular necrosis (AVN) of humeral head during follow-up. Conclusion Treatment of severely impacted valgus proximal humeral fractures with minimally invasive ALA through percutaneous plating PHILOS can avoid the injury of nerve and vascular, reduce the dissection of soft tissue, avoid damage to the residual blood supply of the humeral head and achieve stable fixation, benefiting early function recovery.