Abstract: To get red ginseng in good quality, the existing device for steamed ginseng has been improved and equipped with automatic control unit, in which the temperature of the steamed ginseng can be controlled automatically by the single chip computer. Many comparision tests have been done in the improved device and the existing devices. The experimental results showed that the improved device is better than the former one. It can control variation in temperature ±2℃, saves time and labour, and the quality of steamed red ginseng is good. Meanwhile, improved method is simple, less investment and popularized easily.