To assess the effect of laser frequency and energy setting on outcome in the management of upper ureteric stones by semi-rigid uretroscopy.Study was conducted from June 2015 to June 2017 at our center (in al Hilla teaching hospital). Data of 46 patients were included in our study, these patients complaining from upper ureteric stone (>10mm), our patients were categorized into 2 groups: Group I:(26 patients -26 ureteric stones -) using URS with laser setting (10-15 Hz ,0.5-0.8 J); high frequency low pulse energy with fixed irrigation system. [dusting method] .Group II: (20 patients -24 ureteric stones -included 4 patients with bilateral ureteric stones) using URS with laser setting (4-8 Hz ,1.7-2 J); low frequency high pulse energy with fixed irrigation system. [fragmentation method]Stone size was determined based on the preoperative abdominal ultrasound or CT examinations. (by measuring the longest diameter of the stone)Procedures were done under general or spinal anesthesia after a single dose of pre-operative antibiotic (IV Ceftriaxone) & postoperatively patients done KUB, ultrasonography or unenhanced helical -CT as required at 4th week of follow up to asses stone clearance rate. The total number of our patients was 46 ,They were 28 males and 18 females and their age ranged from 17 to 80 years with a mean age of 46.08 ± 16.61 years ; their stone size ranging from 12 mm to 25 mm (mean of 15.8 mm), they were treated by ureteroscopy and intracorporeal holmium YAG laser lithotripsy. in group I we achieve better result than group II , as stone freedom from single session was 80.7 % in comparison to 70.8 % in group II, also a lower incidence of intra-operative and early post-operative complication, especially stone migration 7.6% Vs 20.8%), and mucosal injury (23.1% Vs 45.8%) ) in group I and group II respectively. The operative time in group I ranged from 40 to 69 minutes (mean: 50.4±3) while in group II it was ranged from 35 to 55 minutes (mean: 40.8 ± 5.3), DJ insertion was (46.2% VS 75%) ) in group I and group II respectively.