It was seen that CLDN10 expression level was negatively related to the infiltrating levels of T cell CD8+ central memory, T cell CD8+ effector memory, T cell CD4+ memory, T cell CD4+ Th1, T cell CD4+ Th2, T cell regulatory (Tregs), B cell plasma, Macrophage M1, Macrophage M2, Plasmacytoid dendritic cell, and Common lymphoid progenitor in STAD, while positively correlated with Cancer associated fibroblast (CAF), Endothelial cell, Eosinophil, Granulocyte−monocyte progenitor and Hematopoietic stem cell (p < 0.05). The gene discussed is CD8A; the disease is cancer.