ix germfree KM mice were obtained by hysterectomy or caesarian section, the young were kept in a germfree environment which is called isolator, and were fed with artificial milk by hand. All newborns were confirmed to be germfree by sterility testing. The feces, bedding and swab are examined for germfree detection, all test samples are negative, this result indicate that the germfree animal feeding are successful. Except above, we analysied nutrition of artificial milk and compared with mother milk of mice.