A randomized controlled study was performed to evaluate the feasibility and outcome of staged versus simultaneous bilateral tubeless PCNL for bilateral renal staghorn stones. A total of 99 patients, with bilateral renal staghorn stones, were prospectively randomized into two groups, and underwent staged tubeless PCNL (49 patients) or simultaneous bilateral tubeless PCNL (50 patients). Preoperative data included urinalysis, urine culture, complete blood count, biochemistry study, renal ultrasonography, intravenous urography, and Tc 99m DTPA clearance for the determination of selective glomerular filtration rate. Intraoperative findings, operative time, and outcome were also recorded. All patients were followed regularly at clinic every 3 months during year 1 and every 6 months thereafter, and Tc 99m DTPA clearance for determination of selective glomerular filtration rate was performed to assess the kidney function 6 months later. There was no difference between the groups with regard to serum creatinine change, hemoglobin decrease, and complication grading. The length of stay, convalescence period, pain visual analog scale, analgesic requirements, and direct cost favored the simultaneous bilateral tubeless group with statistical significance. There was no significant statistical difference in relative perfusion rate between preoperative and postoperative in both groups. This study demonstrates that simultaneous bilateral tubeless PCNL is a safe, efficacious, and cost-effective option in bilateral renal staghorn calculi, which is associated with low morbidity, short hospital stay, high stone-free rate, and early return-to-normal activity.