Urinary bladder calculi comprise 5% of all urinary tract calculi. Giant bladder calculi are defined as a stone more than 100g in weight. However, giant bladder calculus weighted more than 500g is rare in current practice. We present a 60-year-old man who presented with dysuria, difficulty in urination, and suprapubic pain started four years ago. The plain radiology image showed big intravesical caliculi measured about 10x9cm. The calculi was removed via open cystolithotomy without postoperative complication. The caliculi weighed 750g. In conclusion, the main goal of treatment is to remove the calculi and relieve the accompanying symptoms.