Simple Summary Se yeast is a microbial fermentation product created by adding sodium selenite in the yeast cultivation process, which is a superior product of an organic Se source. It exhibits greater bioavailability than the product from inorganic Se sources, and the increased Se levels are maintained for a longer period after the supplementation has ceased. This study evaluated the effects of Se yeast on the growth performance, slaughter performance, antioxidant capacity, and Se deposition in broilers. In conclusion, dietary supplementation of Se yeast can lead to reduced abdominal fat percentages, improved antioxidation function, and increased Se deposition in broiler tissues, thereby enhancing the meat quality of broilers, which holds great significance for the precise production of Se-enriched functional chicken products.Abstract Selenium (Se) yeast, a bioavailable form of selenium, exhibits enhanced bioavailability due to its unique organic matrix and superior metabolic availability compared to the inorganic selenium sources. This study aims to evaluate the effects of Se yeast on the growth performance, slaughter performance, antioxidant capacity, and Se deposition in broiler chickens. A total of 264 1-day-old male AA broilers (38.7 +/- 0.1 g) were randomly assigned to four treatment groups, with six replicates of 11 chickens per replicate. The broilers were fed a basal diet or a diet supplemented with 0.1, 0.2, and 0.4 mg/kg Se yeast. The experiment lasted for 42 days. Although the results showed that Se yeast did not significantly improve the growth performance of broilers, it did significantly decrease the abdominal fat ratio. Additionally, supplementation of Se yeast significantly improved the antioxidant capacity of broilers. The quadratic regression models were used to simulate the relationship between Se content in the feed and Se deposition in broiler tissues. The regression equations were as follows: pectoral muscle, Y = 2.628X - 0.340X2 - 0.592 (R2 = 0.927); leg muscle, Y = 2.317X - 0.272X2 - 0.490 (R2 = 0.937); liver, Y = 3.357X - 0.453X2 - 0.493 (R2 = 0.961); kidney, Y = 4.084X - 0.649X2 + 0.792 (R2 = 0.932). Based on these findings, the Se deposition in broiler tissues can be predicted by the Se content of the additive, which is of great significance for the precise production of Se-enriched functional chicken products.