Objective To improve the results of in vitro fertilization (IVF) for non?obese diabetic (NOD) mice. Methods NOD female mice were divided into four age groups: 4, 6, 8, and 10 weeks old. Sperm from 3 -6?month?old male NOD mice were used for in vitro fertilization. The next day, the number of usable embryos per female mouse was counted and the experiment was repeated twice. NOD mouse embryo transfer data collected from 2016 -2018 were used for the comparison of pup rates. Results Twenty?four hours after the first experiment, the means ± SD of the number of two?cell?stage embryos per group were 13. 4 ±2. 5, 22. 7 ±2. 9, 22 ± 7. 0, and 30. 5 ± 10. 9, respectively. Twenty?four hours after the second experiment, the numbers of two?cell?stage embryos per group were 7. 8 ± 2. 6, 16. 5 ± 4. 5, 14. 2 ± 6. 5, and 24. 5 ±5. 9, respectively. The mean ± SD rates of pups born from transferred embryos after in vitro fertilization in 4, 8, and 10 weeks were (35. 32 ±9. 9)%, (36. 19 ±6. 2)%, and (43. 15 ±6. 9)%, respectively. Conclusions Ten?week?old NOD mice respond better to IVF than 4?, 6?, or 8?week?old ones. Therefore, we suggest the selection of 10?week?old NOD female mice for in vitro fertilization.