Abstract: As the gold standard for infant nutrition, breast milk not only provides infants with abundant nutrients, but also contains prebiotics and active probiotics, which play a crucial role in the establishment of the infant intestinal microecology and the development of the immune system. However, some infants cannot be fully breastfed due to various reasons and need to rely on formula milk powder; currently, most infant formula milk powders do not contain probiotics, making them distinct from breast milk in terms of microecological function. Therefore, it is extremely important to elucidate the mechanism of action of probiotics and to optimize infant formula milk powder. This paper systematically reviews the mechanisms of action of probiotics in infant formula milk powder, including regulating the intestinal flora, enhancing the intestinal barrier function and modulating the immune response. Meanwhile, it analyzes the clinical effects and safety of major probiotic strains and discusses future research directions, aiming to provide a scientific basis for the research, development and clinical selection of infant formula milk powder.

Key words: probiotics; infant formula milk powder; intestinal flora; immune regulation; clinical research

摘要： 母乳作为婴儿营养的黄金标准，不仅能为婴儿提供丰富的营养物质，还含有益生元和活性益生菌，这些成分对婴儿肠道微生态的建立和免疫系统的发育至关重要。然而，部分婴儿因各种原因无法完全接受母乳喂养，需依赖配方乳粉。目前多数配方乳粉缺乏益生菌成分，导致其与母乳在微生态功能上存在显著差异。因此，深入研究益生菌作用机制并优化婴儿配方乳粉具有重要意义。本文系统综述益生菌在婴儿配方乳粉中的作用机制，包括调节肠道菌群、增强肠道屏障功能和调控免疫应答等；评估主要益生菌菌株的临床效果和安全性；探讨未来研究方向，以期为婴儿配方乳粉的研发和临床选择提供科学依据。

关键词: 益生菌；婴儿配方乳粉；肠道菌群；免疫调节；临床研究