Background: Hepatitis B and C are now recognized worldwide as dangerous infectious diseases which impose many physical and economic problems on individuals, families, and society. Objectives: The current research was designed to demonstrate the trends of hepatitis B and C in the south of Fars province, southern Iran, from 2015 to 2021. Methods: The current research was a cross-sectional analytical study. All patients infected with hepatitis B and C from 2015 to mid-2021 were enrolled, and their information was registered in the health department of the Larestan Faculty of Medical Sciences. The Cochran-Armitage trend test was used to determine hepatitis B and C incidences. Results: A total of 306 cases of hepatitis B and 128 cases of hepatitis C were registered. The mean age of the individuals with hepatitis B was 40.15 ± 18.95 years, and that of those with hepatitis C was 45.12 ± 13.31 years. The overall incidence of hepatitis B and C was estimated at 18.44 and 7.71 per 100,000 population, respectively. The highest incidence of hepatitis B was observed, with 50.91 and 26.01 per 100,000 population in 2019 and 2018, respectively, and the lowest incidence was reported in 2016 (1.46 cases per 100,000 population). The highest incidence of hepatitis C, with 17.94 and 15.01 per 100,000 people, was reported in 2018 and 2019, respectively, and the lowest incidence (0.36 per 100,000 population) was in 2016. The finding of the Cochrane-Armitage trend test for both types of hepatitis B and C indicated that the trend of hepatitis incidence from 2015 to 2021 had significantly increased (P Trend < 0.001). Conclusions: In general, the incidence of hepatitis B and C has increased significantly; therefore, it is necessary to implement preventive and control programs.