After introduction, the reproductive condition of Wistar-Imamichi Rats has been surveyed systematically for a year. The results has indicated that the number of induced Wistar-Imamichi rats has been increased from 25 to 3336, forming a fixed scale basic herd. In the aspect of reproductive index, including the pregnant rate, birth rate, the average bodyweight of age of 21 days, the litter size and the sex ratio, the induced rats have kept the same level with the data of original standard Wistar-Imamichi rats. In the period of mass reproduction the induced rats have kept the reproductive biological characteristics of strong reproductive potential and high litter size of the original species.