OBJECTIVES: The aim of this research is to compare the period from 1992 to 1997 to the period from 2012 to 2017, to determine the differences in the number of affected patients and to investigate the incidence of testicular cancer with respect to age. Furthermore, the aim is to analyse data on histological type, localization and size of the tumour and to compare the results with those of worldwide researches. STUDY DESIGN: A retrospective comparative study. PARTICIPANTS AND METHODS: The study included 89 men diagnosed with testicular tumour, 21 in the first period and 68 in the second period. The data were obtained from the archives of the Clinical Institute for Pathology and Forensic Medicine at the Clinical Hospital Centre Osijek and the central hospital archive of the Clinical Hospital Centre Osijek. RESULTS: In the second period there is an increase in the number of tumours, 68 cases compared to 21 cases in the first period. The median age of the diagnosis is 32. In both periods the most common tumour type is seminoma, and right-sided tumour is more common then left-sided. The size of the tumour larger than 4 cm is significantly more frequent from 1992 to 1997. CONCLUSION: By comparing two periods with a 20-year lag, the increase in testicular tumour diagnosis was observed. A specific risk factor has not yet been determined, but the tumour occurs in young adults. Early diagnosis is crucial for a good prognosis.