Urinary stone disease is the third most common problem in urology clinics after urinary tract infections and prostate disease. Objectives: evaluate severity of complications of percutaneous nephrolithotomy (PNL) and open surgery for large renal stones. Patients: 150 adult patients with renal stones more than 2 cm were distributed into two equal groups. Group A had PNL and group B had open surgery. Design: Quasi- experimental research design. Setting Assiut Urology and Nephrology Hospital. Tools: (1) Patient assessment sheet and (2) Clavien-Dindo grading system for classification of surgical complications. Results: No significant relation between the both group regarding complications, stone clearance and need for blood transfusion, while mean hospital stays showed significant relation between the both group. As a group (A) stay only 3.7±1.2 days in hospital after operation while group B stay longer time, 6.1±0.53 days after operation.Conclusions: Open renal surgery for large sized stones still has its role in selected cases with stone clearance and complications rates comparable to PNL. Recommendation: The choice between PNL and open surgery for renal stones should be individualized for each patient.