MicroRNAs (miRNAs) play a critical role in regulating the tumor microenvironment (TME) in gastric cancer (GC), influencing tumor progression and patient prognosis. The TME, which includes fibroblasts, the extracellular matrix, blood vessels, immune cells, and non-cellular components like cytokines and exosomes, significantly affects cancer development, metastasis, and treatment resistance. miRNAs modulate the TME through various signaling pathways, cytokines, growth factors, and exosomes, impacting processes such as cell proliferation, differentiation, angiogenesis, and immune suppression. miRNAs are involved in the regulation of cancer-associated fibroblasts (CAFs), which contribute to tumor progression by secreting ECM proteins, inflammatory ligands, and growth factors. They also regulate immune cells, including Tregs, macrophages, and MDSCs, which can promote tumor growth and immunosuppression. miRNAs can influence the polarization of macrophages, shifting them from M1 (antitumor) to M2 (pro-tumor) phenotypes, thereby enhancing tumor progression. Exosome-derived miRNAs are crucial in intercellular communication, modulating the TME and influencing GC development, metastasis, and drug resistance. miRNAs can regulate immune checkpoint ligands, such as PD-L1, and affect T-cell activity, which is essential for immunotherapy. Additionally, miRNAs can modulate the expression of immune-related genes and influence the tumor's response to chemotherapy. The dysregulation of miRNAs is associated with various aspects of GC, including angiogenesis, EMT, and resistance to therapy. miRNAs have emerged as potential biomarkers and therapeutic targets for GC, offering new insights into the complex interactions within the TME. Understanding the role of miRNAs in the TME is crucial for developing targeted therapies and improving patient outcomes. Despite progress, challenges remain in translating these findings into clinical applications, including the need for more detailed understanding of miRNA functions in different cell types and the development of effective delivery systems for miRNA-based therapies.MicroRNAs (miRNAs) play a critical role in regulating the tumor microenvironment (TME) in gastric cancer (GC), influencing tumor progression and patient prognosis. The TME, which includes fibroblasts, the extracellular matrix, blood vessels, immune cells, and non-cellular components like cytokines and exosomes, significantly affects cancer development, metastasis, and treatment resistance. miRNAs modulate the TME through various signaling pathways, cytokines, growth factors, and exosomes, impacting processes such as cell proliferation, differentiation, angiogenesis, and immune suppression. miRNAs are involved in the regulation of cancer-associated fibroblasts (CAFs), which contribute to tumor progression by secreting ECM proteins, inflammatory ligands, and growth factors. They also regulate immune cells, including Tregs, macrophages, and MDSCs, which can promote tumor growth and immunosuppression. miRNAs can influence the polarization of macrophages, shifting them from M1 (antitumor) to M2 (pro-tumor) phenotypes, thereby enhancing tumor progression. Exosome-derived miRNAs are crucial in intercellular communication, modulating the TME and influencing GC development, metastasis, and drug resistance. miRNAs can regulate immune checkpoint ligands, such as PD-L1, and affect T-cell activity, which is essential for immunotherapy. Additionally, miRNAs can modulate the expression of immune-related genes and influence the tumor's response to chemotherapy. The dysregulation of miRNAs is associated with various aspects of GC, including angiogenesis, EMT, and resistance to therapy. miRNAs have emerged as potential biomarkers and therapeutic targets for GC, offering new insights into the complex interactions within the TME. Understanding the role of miRNAs in the TME is crucial for developing targeted therapies and improving patient outcomes. Despite progress, challenges remain in translating these findings into clinical applications, including the need for more detailed understanding of miRNA functions in different cell types and the development of effective delivery systems for miRNA-based therapies.