This experiment was conducted to study the effects of dietary fat level on growth performance, nutrient digestibility and nitrogen metabolism of silver foxes in growing period. Fifty male silver foxes aged about 12 weeks with similar body weight were randomly divided into 5 groups with 10 replicates per group and 1 fox per replicate, they were fed experimental diets supplemented with 8% (group Ⅰ), 10% (group Ⅱ), 12% (group Ⅲ), 14% (group Ⅳ) and 16% (group Ⅴ) mixed oil (chicken oil：soybean oil=1：1), and the corresponding dietary fat levels were 9.9%, 11.7%, 13.3%, 15.6% and 17.4%, respectively. The adaptation period lasted for 20 days and the formal period lasted for 55 days. The results showed as follows: 1) dietary fat level had no significant effects on the average daily gain, dry matter intake, daily metabolizable energy intake and feed/gain (P>0.05). 2) Dietary fat level had a significant effect on the digestibility of fat (P<0.01), gross energy (P<0.05) and carbohydrate (P<0.01), but had no significant effect on the digestibility of dry matter and protein (P>0.05). The digestibility of fat and gross energy was increased with dietary fat level increasing, while the digestibility of carbohydrate was declined. Compared with group Ⅴ, the digestibility of fat and gross energy in group Ⅰ was increased by 11.48% (P<0.01) and 4.98% (P<0.05), respectively, while the digestibility of carbohydrate was decreased by 12.41% (P<0.01). 3) Dietary fat level had no significant effects on nitrogen intake and fecal nitrogen (P>0.05), but had significant effects on urea nitrogen, nitrogen retention, net protein utilization and biological value of protein (P<0.01). The urea nitrogen in group Ⅴ was the highest and that in group Ⅰ was the lowest, and a significant difference was found between groups Ⅴ and Ⅰ (P<0.01); the nitrogen retention, net protein utilization and biological value of protein in group Ⅰ were the highest and those in group Ⅴ were the lowest, and significant differences were found between groups Ⅰ and Ⅴ (P<0.01). Considering all indices, the 8% is considered to be an optimal supplemental level of mixed oil in the diet (dietary fat level is 9.9%) for silver foxes in terms of reducing feed expenses and environmental pollution, and maintaining growth performance.