The results indicated that the polysaccharides of Cornus officinalis exhibited a substantial tumor inhibitory effect on S180 (p < 0.01), with the potential to enhance the expression of peripheral blood CD4+ T cells, decrease the expression of CD8+ T cells, increase the level of interleukin IL-2, and reduce the level of interleukin IL-4. This evidence concerns the gene CD8A and neoplasm.