Abstract: Objective The purpose of the study is to breed homozygous interferon-γ knockout ( IFN-γ- / -)mice and optimize the breeding strategies to achieve continuous and stable reproduction of IFN-γ- / - mice, which could be used as an ideal animal model for fundamental research. Methods Initially, heterozygous IFN-γ knockout (IFN-γ+ / -) C57BL / 6J mice were used as the parental generation for breeding. Subsequently, 3 breeding strategies were employed using the offspring: (1) female heterozygotes mated with male heterozygotes; (2) male homozygotes mated with female heterozygotes; (3) female homozygotes mated with male homozygotes. The number and survival rate of IFN-γ- / - mice were compared across the three breeding strategies to determine the optimal breeding strategy. Under the optimal strategy, the effects of female mating age and diet type on the reproductive performance of IFN-γ- / - mice were further evaluated. Data from the first three litters of 60 IFN-γ- / -emale mice, including litter size, number of weaning survivors, and weaning survival rate, were recorded and analyzed. In addition, the effects of dietary supplementation of pregnant mice and environmental optimization measures, such as the provision of shelters, were evaluated. Results Under conditions where the nutritional needs of pregnant mice were adequately met by supplementation with egg yolk and sunflower seeds, mating of female and male IFN-γ- / - mice result ed in a litter size of five to eight IFN-γ - / - mice, demonstrating higher efficiency compared to other breeding strategies. In addition, diet type and mating age significantly influenced female reproductive performance. When 7 ~ 9 weeks old female IFN-γ- / - mice were mated to male IFN-γ- / - mice and fed a high-protein breeding diet, litter size ( 6. 9 ± 1. 7), weaning survival number (6. 5% ± 2. 0%) and weaning survival rate (93. 2% ± 17. 8%) were higher than those under other conditions. In addition, providing shelters to prevent fighting between breeding pairs further improved reproductive outcomes. Conclusions By adopting an optimized breeding strategy, combined with a high-protein diet, nutritional supplementation, and standardized mating age management, the breeding efficiency and stability of IFN-γ- / - mice can be significantly improved. This provides a reliable animal model for related research.