This paper is based on the presentation of treating prostate cancer with radiotherapy. Prostate carcinoma is the second most common carcinoma in men based on incidence, it is also the second most common carcinoma based on the mortality rate in men. Given the above a great number of ill people demand opportune, as early as possible diagnosis. The methods used in setting a diag-nosis are: determining the value of prostate specific antigen, transrectal ultrasound, CT and MRI of the pelvis. In the end the diagnosis is set with a pathohistological confirmation of the illness. Based on imaging we determine the clinical, and based on pathohistology the pathohistological stage of the illness. Given the stage of the illness we can divide it as localized, locally spread and metastatic illness of the prostate, and based on that division we can decide on a treatment modali-ty. In the case of a localized illness we can apply radical prostatectomy, radical radiotherapy or we can seldom actively monitor the patient. Prognostic markers in the case of prostate carcinoma, such as the value of PSA, Gleason's score, the patients general condition, comorbidity and the results of diagnostic imaging determine treatment modality. Radiotherapy treatment of people with prostate carcinoma presents the basis of treating, localized or spreaded symptomatic illness. The success rate of treating localized illness is exceptional, the survival rate of patients with low stage illness is expected to be 90% survival for 15 years.