This study was intended to roast freeze-dried ginseng in order to determine the effect of roasting conditions on major ginsenosides by monitoring their changes using response surface methodology. As the roasting temperature and time increased, the contents of ginsenoside Re, $Rg_1$, Rf, $Rb_1$, Rc, $Rb_2$, and Rd tended to decrease but that of ginsenoside $Rg_3$ increased, reaching the maximum content (0.96 mg/g) at $189.99^{circ}C$ and 20.29 min as compared to the initial value (0.01 mg/g). The total ginsenoside content was estimated to be increased from 4.30 to 5.19 mg/g at $140.17^{circ}C$ and 27.51 min. It was found that the roasted ginseng has different ginsenoside compositions from raw ginseng. Therefore, further studies are needed to investigate the functional and biological properties of roasted ginseng as compared to the conventional white and red ginseng.