Objective: To evaluate the results of antibiotic prophylaxis in treatment of middle and distant ureteral stone by ureteroscopy. Subject and method: 54 case of middle and distant ureteral stone treated by ureteroscopy from October 2013 to June 2014 in Urology Department of 108 Military Central Hospital with antibiotic prophylaxis Cefotaxime 2g via intravenous single dose 30 minutes before surgery. The eligible criteria: patients without urinary tract infection on clinical findings and laboratorial testing. Follow-up 24h after surgery: fever, blood counts, procalcitonin (PCT), urine culture, urine microscopy and urinalysis. Result: 24 hours after surgery: Fever in 1 patient (1.8 percent), white blood cells increased in 45/53 of patients (83.3 percent), PCT increased in 33/54 of patients (61.1 percent). Urinary nitrites testing and urine culture were negative in 54/54 of patients (100 percent). The presence of red blood cells and white blood cells in urine were 91.8 percent and 70.3 percent, respectively. Conclusion: Cefotaxime used as antibiotic prophylaxis in treatment of distant and middle ureteral stone by ureteroscopy achieved good results (98.15 percent). Antibiotic prophylaxic can replace surgical antibiotic coverage for patients without urinary tract infection, ureteral stones size 20 mm, short operation time without surgical complications.