Antibiotic resistance is looming problem in broiler production globally and there has been an increasing interest to look for sustainable alternatives to antibiotics. Yeast and its derived products are recognized as potential feed additives because of their beneficial impacts on poultry. Particularly, yeast exhibited positive effects on the humoral immunity by increasing serum immunoglobulin (Ig) A levels. Moreover, yeast and its products showed immune adjuvant-like properties that helped the broilers chicken to develop faster and stronger innate immune response under pathogenic challenges. Use of yeast and its products as prebiotic/probiotic improves the gut architecture mainly by improving the gut development and gut microbiome, reduction in colonization of pathogens through competitive exclusion, binding of toxins and enhancing digestion and absorption of nutrients. These unique properties of yeast and yeast products enhance animal welfare and productivity; warrant them to be used as a promising feed additive. This article, therefore, provides insights into the functional role of yeast and its products in the broiler diets and highlights its importance as a commercially viable alternative of synthetic antibiotic growth promoters in the broiler feed industry.