As the intricate interplay between microbiota and the host garners increasing research attention, a significant parallel surge has emerged in the investigation of intestinal bacterial extracellular vesicles (BEVs). Most intestinal bacteria secrete BEVs, which harbor specific cargo molecules and exhibit diverse functions, encompassing interactions among bacteria themselves and between bacteria and the host. These interactions can either bolster host health or contribute to various pathologies. By integrating the characteristics of BEVs, we summarized the current research landscape, delving into the intricate interplay between BEVs and different diseases. Furthermore, we offer a succinct overview of the challenges faced in BEVs-based research, encompassing separation, detection, engineering for drug purposes, clinical diagnostics, safety, and future study. In essence, these summaries may serve as invaluable guides for BEVs as communication tools between the gut microbiome and host, ultimately propelling the discovery of novel studies and drug discovery.