Anahtar KelimelerKomplikasyon; Perkütan Nefrolitotomi; Kanama; Litotripsi; Nefrostomi Abstract Aim: Today, PNL has become primary treatment alternative in multiple or large kidney stones where ESWL treatment has failed. In our study, we have analyzed the facts that affect hemorrhage in PNL surgeries. Material and Method: Between March 2008 and December 2009, 204 patient's histories who had undergone percutaneous nephrolithotomy surgery in Izmir Bozyaka Training & Research Hospital, Urology Department were analyzed retrospectively. The patients were assembled under four groups according to the effect of some factors related to stone (size and localization), operation (number and localization of the entrances) and the effects of PNL hemorrhage between these groups was investigated. Results: Of the 204 patients undergoing percutaneous nephrolithotomy, 76 were female, 128 were male, with an average age of 46. 9±14.2 (18-80). The preoperation and postoperation Hb differences of the 176 patients whose stone load was less than 1000 mm2 and 28 patients whose stone load was over 1000 m2 were compared, yielding no statistically significant difference (p=0.942). Also no statistically significant difference was observed with regard to stone type, number of entries and percutaneous entry location. Discussion: In our study, it has been observed the size and localization of the stone is not an independent factor that affects the hemorrage itself. And also it has been observed that number and localization of entrances are not an independent factor that affecting haemorrhage.