Abstract: The descent of testicles and reproduction of Meriones meridianus jei and Cricetulus migratorius in breeding rooms were observed in four conditions ：under the artificial illumination with a regime of D8 : L16 at temperature 15～20℃ or 10～14℃，and utilizing the sun-shine with a regime of Dll. 5～15 : L12. 5～9 at two temperatures mentioned above. The results showed that both M. meridianus and C. migratorius belong to the rodents of long sunshine type. With the lighting regime D8 : L16,raising temperature could lead the testes to descend,and the copulations were effective by more than 43d and 21d’s stimulating (15～20℃) in M. meridianus jei and C. migratorius respectively. With the lighting regime Dll. 5～15 : L12. 5～9，raising temperature could stimulate the testes to descend in C. migratorius that could also take part in reproduction by more than 60d’s stimulating (1.5～20℃) »but not in M. meridianus jei.

Key words: Temperature, Light - dark cycle, Descensus testis, Reproduction, Meriones meridianus, Cricetulus migratorius