The majority of laboratory animals were transported from commercial breeders to a research facility by ground transportation. During the transportation, many biological functions and systems can be affected by stress. In this experiment, the change of body weight during the transportation was measured and the recovery periods from the transportation stress established based on the body weight changes. Total 676 laboratory animals which were aged between 3 to 9 wk old were studied. The transportation time taken from container packing to unpacking the container was approximately 24 h. The temperature of animal container was constantly maintained by air-conditioning and heating equipment. Rats were found to be more sensitive than mice. The body weight of rats was significantly decreased 3.71% (p<0.05) compared to the body weight of mice which decreased 0.9% There was no significant difference between the strains in the same species. When the changes of body weights were compared between delivery days, C57BL/6 mice showed the most variable changes compared to other species and strains. Consequently, C57BL/6 was more sensitive to stress than the other strains and the transportation process needs to be standardized to reduce between day variability. To establish the recovery periods from transportation stress, the body weight changes were measured during the acclimation period. Although the body weight of animals decreased during transportation, animals recovered their weight loss after the next day.