This review comprehensively evaluates the effects of bay leaf (Laurus nobilis L.) powder on gut microbiota, intestinal epithelial integrity, and barrier functions in animal production, in light of current scientific literature. Maintaining gut health and intestinal barrier integrity plays a critical role in animal welfare, growth performance, and immune function in modern animal production. With the restriction of antibiotic growth promoters, phytobiotic feed additives such as bay leaf have emerged as natural and safe alternatives. Bay leaf exhibits high biological activity due to its rich content of bioactive compounds, including volatile oils, phenolic compounds, and flavonoids, particularly 1,8-cineol. These bioactive components suppress pathogenic loads in the gut microbiota while promoting beneficial bacterial populations and short-chain fatty acid (SCFA) production. Increased SCFA levels optimize the metabolism of intestinal epithelial cells and functionally strengthen barrier integrity by increasing the expression of tight junction proteins. Furthermore, the antioxidant and anti-inflammatory properties of bay leaf help regulate oxidative stress, limit cellular damage and pro-inflammatory processes in epithelial tissue. Consequently, bay leaf stands out as a strategic phytobiotic additive with the potential to support gut health, maintain microbial balance, and enhance intestinal barrier integrity in sustainable animal production.