Background: We investigated the protective effects of rosmarinic acid (RA) on testicular damage induced by doxorubicin (DXR) in rats. Methods: In total, 21 rats were divided into 3 groups: the control group that received no treatment, the DXR group that received intraperitoneal (i.p.) DXR on day 7 and the DXR + RA group that received intragastric RA for 10 days with i.p. DXR on day 7. The rats were sacrificed on day 11 for histological and biochemical analyses. To assess oxidative damage, glutathione peroxidase (GPx) and malondialdehyde (MDA) levels were measured. Results: The median modified Johnsen score of the DXR + RA group was higher than that of the DXR group (p = 0.002). The rats with the narrowest seminiferous tubules were in the DXR group (0.17 ± 0.03), and the difference between the DXR + RA and DXR groups was statistically significant (p = 0.002). The number of apoptotic cells in the DXR group was significantly higher than that in the control group, and there were significantly fewer apoptotic cells in the DXR + RA group than in the DXR group (p = 0.002). The MDA level was lowest in the control group and highest in the DXR group, and the level observed in the DXR + RA group significantly lower than that in the DXR group (p = 0.002). The GPx level was highest in the control group, with the level observed in the DXR + RA group significantly higher than that in the DXR group (p = 0.002). The testosterone level was lowest in the DXR group and highest in the control group, and that observed in the DXR + RA group was significantly higher than that in the DXR group (p = 0.018). Conclusions: RA can correct DXR-induced testicular damage through its antioxidant properties. However, the mechanism underlying the effects of RA requires further investigation, and long-term and comparative human studies are also needed.