Oral squamous cell carcinoma (OSCC) is a prevalent cancer that needs new therapeutic targets due to the poor postoperative prognosis in patients. Exosomes are currently one of important research areas owing to their unique properties. Exosomes are capable of acting as drug transporters, as well as facilitating interactions between OSCC and normal cells. Exosomes can be detected in body fluids such as blood, urine, cerebrospinal fluid, and bile. When exosomes are released from donor cells, they can carry various bioactive molecules to recipient cells, where these molecules participate in biological processes. This review highlights the mechanisms of exosome transfer between normal and OSCC cells. Exosomes isolated from donor OSCC cells can carry circular RNAs (circRNAs), long non-coding RNAs (lncRNAs), and microRNAs (miRNAs) and play a role in signaling processes in the recipient OSCC cells, human umbilical vein endothelial cells, and macrophages. Exosomes secreted by carcinoma-associated fibroblasts, macrophages, and stem cells can also enter the recipient OSCC cells and modulate signaling events in these cells. Exosomes isolated from OSCC plasma, serum, and saliva are also associated with OSCC prognosis. Furthermore, while exosomes were shown to be associated with chemotherapy resistance in OSCC, they can also be used for drug delivery during OSCC treatment. In this paper, we reviewed the molecular mechanisms and functions of exosomes from different cell sources in OSCC cells, providing a basis for diagnosis and prognosis prediction in OSCC patients, and offering guidance for the design of molecular targets carried by exosomes in OSCC.