Objective To determine the main reproductive performance of six SPF mice and rats preserved in our laboratory, including C57BL/6, BALB/c, NIH, KM, ICR mice and SD rats.Methods Inbred mice mated with full sib and random mating.Meanwhile, closed colony animals were bred by cross circular mating.These indexes of reproductive performance were measured in the six kinds of animals during the first birth to the fourth birth, i.e.the average litter size (ALZ), average baby number reared ( ABN) and average weaning number ( AWN), and weaning rate ( WA) were calculated.Meanwhile, the initial mating age in days, initial bearing age in days, first gestation and intervals were measured.Results The ALZ of inbred mice were 6 to 7.The reproductive indexes were basically stable in the first 3 births, however, the various data were dramatically declined in the fourth birth ( P<0.05 ) .The WA of BALB/c mice were 98%to 99%, and that of C57BL/6 mice were 96%to 98%.The ALZ of closed colony animals were 12 to 15, and significantly increased in the second and third births compared with that of the first birth (P<0.05), then was significantly reduced ( P<0.05) .The WA maintained at 98%to 99%in the NIH, KM and ICR mice.In contrast, The WA of SD rats was slightly lower, reaching 95%to 97%.The initial mating age in days of mice was between 70 d to 80 d.The initial bearing age in days and first gestation of rats were less than that of inbred mice, the initial bearing age in days and first gestation of closed colony rats were 136.3 d and 27.7 d, respectively.The pregnancy interval of inbred mice was between 34 d to 40 d,the pregnancy interval of closed colony mice was between 25.5 d to 28.7 d, the pregnancy interval of rats was between 32.8 d to33.8 d.Conclusions The 6 mouse and rat strains have a higher reproductive performance, and the data obtained in this study provide a basis for commercialized production of mice and rats in southern areas of China, and for establishment of rodent experimental animal resource.