Background/Aim. Although radiotherapy is considered to be a standard treatment of stage A testicular seminoma, an increasing number of studies have reported encouraging results of the treatment by carboplatin monochemotherapy (CBDCA). The aim of this study was to analyse the treatment results of patients with clinical stage A seminoma treated by CBDCA on daily basis in the period June 1999 to September 2008. Methods. A total of 124 patients, mean age 36.63 years (20-62 years), with stage A testicular seminoma were treated, upon radical orchiectomy, by adjuvant CBDCA (400 mg/m2 on day 1 and 22). Results. Chemotherapy was well tolerated, except moderate nausea on the day of the drug administration and the following day. No patient had any serious disorders in blood cells count requiring substitutional treatment. During the mean follow-up period of 37.5 (range 6-111) months, three relapses were noted (2.41%) and none neoplasm of contralateral testicle or any other organ. Conclusion. Simple and easy carboplatin administration with excellent treatment results, along with good tolerance and absence of comorbidity, poses itself as a new 'gold standard' of treatment for stage A testicular seminoma.