The aim of this work was to evaluate the effect of resveratrol (RSV) during liquid storage of stallion sperm for 24 hours at either 10°C or 4°C. The antioxidant RSV was added to reduce the oxidative damage that occurs during cold storage. Aliquots of 2 mL of diluted semen were stored either at 4°C or 10°C under anaerobic conditions, in the absence (control group) or presence of RSV at different concentrations (10, 20, 40, and 80 μM). Sperm quality parameters were assessed at 0 hours and after 24 hours of storage. Resveratrol treatment did not affect sperm quality parameters at 0 hours. At 24-hour storage, a significant (P < .01) decrease of sperm quality was observed independently from RSV supplementation and storage temperature. A significant decrease of viable spermatozoa with high mitochondrial membrane potential (SYBR+/PI−/JC-1+) was evident at 24-hour storage in 40- and 80-μM RSV groups compared with control group. Moreover, a decline of total motility in 80-μM RSV group compared with the control group and a decrease of progressive motility and average path velocity in 80-μM RSV group compared with control and 20-μM RSV groups were observed. In conclusion, our findings demonstrate that RSV supplementation does not enhance sperm quality of stallion semen after 24 hours of storage. Moreover, 40- and 80-μM RSV concentrations could damage sperm functional status, probably acting as pro-oxidant. Finally, although 24-hour storage significantly affected most of the sperm quality parameters, no significant differences were found in groups maintained at 4°C or 10°C, suggesting that stallion semen could be equally preserved at these different temperatures.