Research Objective: This study presents the incidence of syphilis and gonorrhoea in the Osijek-Baranya County, its comparison with the incidence of those diseases in the Republic of Croatia, a comparison of the number of syphilis and gonorrhoea cases registered in the Epidemiological Office in Osijek with the number of appertaining cases in other epidemiological field offices in the Osijek-Baranya County, a comparison of the incidence of syphilis and gonorrhoea with respect to age categories and case distribution regarding age and gender. Study Design: The data were retrospectively analysed during a 17-year period: from 2000 to 2016. Materials and Methods: The study included 48 examinees who were suffering from syphilis and gonorrhoea. The data about the patients were extracted from the database of the Institute of Public Health of the Osijek-Baranya County. The author also used information found in the Croatian Scientific and Statistical Yearbooks for the years 2006 and 2016 as well as data from the 2001 and the 2011 census. The data were analysis according to age, gender and site field. Results: The incidence rate of syphilis in the Osijek-Baranja County in the period from 2000 to 2010 amounted to 3/100,000 and the incidence rate of gonorrhoea to 7.9/100,000. In the period from 2011 to 2016, the incidence rate of syphilis dropped to 1.6 patients per 100,000 inhabitants, and of gonorrhoea to 2.3/100,000. In the last 17 years, there has been a decrease in the incidence of syphilis and gonorrhea. Osijek is characterized by a lower incidence rate of syphilis and a higher incidence of gonorrhoea with respect to the rest of the County (epidemiological field offices in the Osijek-Baranja County). There are no statistically significant differences in the number of patients suffering from these two diseases between man and women, and between different age categories. Conclusion: The incidence of syphilis and gonorrhoea in the Osijek-Baranya County is declining. Better control of these diseases can be achieved with further, continuous monitoring and analysis of incidence tendencies.