Swimming enhancing effects of ssanghwatang fermented with Saccharomyces cerevisae in mice were investigated, and then the blood biochemical parameters related to fatigue were measured. Compared to the control group, the swimming time was significantly increased in fermented ssanghwatang (FST) group from day 4 ($29.27{pm}4.73$ vs. $50.27{pm}9.05;min$, p<0.05). The lactate level, an important indicator of fatigue, was drastically lower in FST group than in control group ($2.13{pm}0.13$ vs. $1.40{pm}0.12;mmole/L$, p<0.01). These results suggest that FST possesses stimulatory effects which can enhance exercise performance and reduce fatigue.