Cell-cell communication is essential for the regulation of various biological phenomena in multicellular organisms, including development and homeostasis. Deregulation of these interactions leads to inappropriate cell-cell communication, resulting in disease development. Cancer cells communicate closely with the cells in their microenvironment, and this communication promotes malignancy via abnormal growth, invasion, drug resistance and metastasis. Understanding cell-cell interactions in cancer is essential for the development of novel anticancer agents. As a result, discovering the communication tools used by cancer cells is important to understanding these interactions. In this review, we summarize the recent findings regarding exosome-mediated cancer development. In addition, we propose that targeting the exosome represents a novel strategy for cancer therapy.