Implementation of IMRT offers possibility to escalate radiation therapy dose without increased acute and late toxicity. The aim of this study is to compare acute and late genitourinary and gastrointestinal toxicity in patients treated with IMRT and 3DCRT technique. This study included 35 patients in study group A treated with IMRT technique, and 35 patients in study group B treated with 3DCRT technique. Patients were selected and referred to radical radiotherapy treatment prostate cancer. Acute genitourinary and gastrointestinal toxicity was evaluated during radiotherapy treatment according to recommendation of RTOG group. Late gastrointestinal and genitourinary toxicity was evaluated during regular control exams after radical radiotherapy treatment for six months. Based on the results χ2 test there was no statistical significant difference (p>0,05) between study group A i B in terms of acute gastrointestinal and genitourinary despite escalated radiotherapy dose in study group B treated with IMRT technique. Based on the results χ2 test there was no statistical significant difference (p>0, 05) between study group A i B in terms of late gastrointestinal and genitourinary toxicity. Intensity modulated radiation therapy is optimal technique in the radical treatment prostate cancer. This technique allows clinical benefit compared with 3D conformal radiotherapy-escalation of radiotherapy dose without increased toxicity in patients treated with IMRT technique.