This sterilizer enables to sterilize surgical instruments and dressings at minimum expenses by a germicidal lamp generating the ultraviolet rays of 253.7nm wavelength which has the most powerful germicidal effect and dry heat of 120?. Ultraviolet rays is effective in killing all germs, but the resistance of germs varies depending on their kinds. Escherichia coil are stamped out within a minute 50cm away from the germicidal lamp of 15W, and within 6 seconds 10cm away from the germicidal lamp, while dysentery bacillus, typhoid bacillus and a variety of virus are exterminated within even shorter period of time. This sterilizer has several functions such as automatic temperature control, time setting and selecting of sterilization methods out of heater, germicidal lamp and both. Therefore it is easy and safe to use. If the medical device and materials processed with the Steam, Dry Heat or Gas sterilizer are stored long time, they are likely to be contaminated again. In this case, if this sterilizer is used, it is possible to prevent them from being contaminated again.