Abstract: This experiment was conducted to assess the effects of dietary supplementation of peony seed cake with different proportions on growth, digestion and slaughter performance of growing-finishing pigs. A total of 40 crossbred（Duroc×Yorkshire×Landrace） pigs with approximately 50 kg of body weight were randomly assigned to four groups： experiment Ⅰ group served as control and fed basil diet, experiment Ⅱ, Ⅲ, Ⅳ groups received 2%, 5%, 8% of peony seed cake supplementation in basil diet;different groups had the same nutrition level of the diet, and the pre-experiment and formal experiment lasted for 10 days and 35 days, respectively; at the end of the experiment, the indexes associated with growth, digestion and slaughter performance of the growing-finishing pigs in different groups were determined and statistically assessed. The results demonstrated that the average daily gain of experiment Ⅲ and Ⅳ groups reached up to 972.00 g and 974.29 g respectively and was significantly higher than that of control group（P〉0.05）; the lowest feed/gain ratio was observed in experiment Ⅲ group followed by experiment Ⅳ group, but no group differences were found（P〉0.05）; the experiment Ⅲ group had the highest digestibility of dry matter, crude protein and crude fat, and the experiment Ⅰ group had the highest digestibility of crude fiber, but no group differences in the digestibility of nutrients were observed（P〈0.05）; there were no significant differences in pre-slaughter live weight, carcass weight, dressing percentage and eye muscle area between different groups（P〈0.05）. Taken together, we concluded that the dietary supplementation of peony seed cake has no affection on growth, digestion and slaughter performance of growing-finishing pigs;furthermore, an improving tendency of the associated indexed is observed, and the 5% supplementation proportion of peony seed cake is recommended by this study.