Tumor microenvironment has been confirmed to play an important role in the occurrence, invasion and metastasis of many kinds of tumors. Carcinoma-associated fibroblasts (CAFs) are the primary type of host cells in the tumor microenvironment. CAFs have an assignable role in tumor development. CAFs create a suitable "soil" for tumor origination, secrete a large amount of growth factors promoting tumor growth and angiogenic factors promoting tumor angiogenesis. In addition, CAFs attract a large number of inflammatory cytokines, and secrete a great quantity of soluble products promoting tumor cell invasion and metastasis. Therefore, CAFs may become new targets for targeted cancer therapy, and provide new ideas for the clinical cancer comprehensive treatment.