Earlier studies have reported right-sided lateralization for different organ cancers except breast cancer. In the present study, lateralization of head-neck cancers and their relation with the peripheral cell-mediated immune asymmetry was investigated. The sample was comprised of 42 men and 20 women diagnosed with cancer in the head-neck region. The diagnosis of cancer was made histopathologically. To measure the cell-mediated (type IV) immunity of both forearms, the tuberculin test (PPD test) was used in the subjects previously sensitized by BCG vaccine during the first year of age. Significant right-sided lateralization in men and the significant left-sided lateralization in women were observed in this study. There was no relation between the lateralization of cancer and the asymmetry of tuberculin reaction or the peripheral cell-mediated immune asymmetry.