Gastric cancer (GC) is a common and frequent malignant cancer of the digestive system with a poor prognosis. In addition to common therapies such as surgical resection and chemotherapy, novel biological interventions are quite valuable for research. Exosomes are extracellular vesicles (EVs) that originate from various cell types and contain proteins, RNA, DNA, and other components that transmit biological signals and mediate intercellular communication. Numerous studies have shown that exosomes shape the tumor microenvironment (TME) by affecting hypoxia, inflammation, immunity, metabolism, and interstitial changes in the tumor, playing a crucial role in the development and metastasis of GC. This article reviews the important role of exosomes in the TME of GC and explores their potential clinical applications in GC treatment.