Purpose: The basic idea of combination chemotherapy is to eradicate tumor cells through potent therapy before the appearance of resistant cells or an elevation in the number of the resistant cells. This article explores the use of combination chemotherapy in the treatment of solid tumors in head and neck. Method: The efficacy of chemotherapy for head and neck tumors is specifically reviewed. Results: Several hypotheses are generally well known and accepted as basic theories in cancer chemotherapy, and researchers have developed effective combination chemotherapy regimens based on these theories. Chemoradiotherapy was initially developed to regulate the local tumor through radiation and control distant metastases through chemotherapy. The purpose of adjuvant chemotherapy is to treat latent tumor cells that cannot be seen macroscopically after completion of first-line therapy. Continuous administration of a small dosage is a new concept that has recently been proposed to replace the conventional concept of total cell-killing. Conclusion: This article examines the use of combination chemotherapy in the treatment of solid tumors and reviews the efficacy of chemotherapy, which should be understood by head and neck surgeons.