The gut microbiota plays a critical role in immune responses and cancer immunotherapy. Recent research has shown that the gut microbiota influences the effectiveness of cancer immunotherapy, particularly through its interactions with the immune system. The gut microbiota can affect immune-related adverse events and has the potential to be a target for precision cancer immunotherapeutics. This review discusses the complex interactions between the gut microbiota, the immune system, and immunotherapy in the context of cancer. It also explores potential interventions to minimize adverse effects and discusses five microbiota-targeted strategies that can enhance the efficacy of cancer immunotherapy. The review highlights the importance of understanding the functional role of the gut microbiota in regulating immune responses to cancer immunotherapy and the challenges in this field. The gut microbiota is essential for maintaining intestinal barrier integrity and homeostasis, and its composition is under the surveillance of the intestinal immune system. The review also discusses the role of the gut microbiota in the development of immune cells, such as T cells, B cells, and macrophages, and how microbial metabolites can influence immune responses. The review emphasizes the importance of understanding the gut microbiota's role in cancer immunotherapy and the need for further research to develop effective interventions. The gut microbiota has been shown to play a critical role in the development of immune responses and cancer immunotherapy, and its modulation can enhance the efficacy of cancer immunotherapy. The review also discusses the potential of microbial metabolites, such as short-chain fatty acids (SCFAs), in modulating immune responses and cancer immunotherapy. The review highlights the importance of understanding the gut microbiota's role in cancer immunotherapy and the need for further research to develop effective interventions. The gut microbiota has been shown to play a critical role in the development of immune responses and cancer immunotherapy, and its modulation can enhance the efficacy of cancer immunotherapy. The review also discusses the potential of microbial metabolites, such as short-chain fatty acids (SCFAs), in modulating immune responses and cancer immunotherapy. The review highlights the importance of understanding the gut microbiota's role in cancer immunotherapy and the need for further research to develop effective interventions.The gut microbiota plays a critical role in immune responses and cancer immunotherapy. Recent research has shown that the gut microbiota influences the effectiveness of cancer immunotherapy, particularly through its interactions with the immune system. The gut microbiota can affect immune-related adverse events and has the potential to be a target for precision cancer immunotherapeutics. This review discusses the complex interactions between the gut microbiota, the immune system, and immunotherapy in the context of cancer. It also explores potential interventions to minimize adverse effects and discusses five microbiota-targeted strategies that can enhance the efficacy of cancer immunotherapy. The review highlights the importance of understanding the functional role of the gut microbiota in regulating immune responses to cancer immunotherapy and the challenges in this field. The gut microbiota is essential for maintaining intestinal barrier integrity and homeostasis, and its composition is under the surveillance of the intestinal immune system. The review also discusses the role of the gut microbiota in the development of immune cells, such as T cells, B cells, and macrophages, and how microbial metabolites can influence immune responses. The review emphasizes the importance of understanding the gut microbiota's role in cancer immunotherapy and the need for further research to develop effective interventions. The gut microbiota has been shown to play a critical role in the development of immune responses and cancer immunotherapy, and its modulation can enhance the efficacy of cancer immunotherapy. The review also discusses the potential of microbial metabolites, such as short-chain fatty acids (SCFAs), in modulating immune responses and cancer immunotherapy. The review highlights the importance of understanding the gut microbiota's role in cancer immunotherapy and the need for further research to develop effective interventions. The gut microbiota has been shown to play a critical role in the development of immune responses and cancer immunotherapy, and its modulation can enhance the efficacy of cancer immunotherapy. The review also discusses the potential of microbial metabolites, such as short-chain fatty acids (SCFAs), in modulating immune responses and cancer immunotherapy. The review highlights the importance of understanding the gut microbiota's role in cancer immunotherapy and the need for further research to develop effective interventions.