KAI1/CD82 is a metastatic suppressor gene in human prostate cancer and several other types of cancer in humans. The present study aimed to examine the role of the overexpression of KAI1 in the progression of oral cancer. Human KAI1/CD82 cDNA was transfected into OSCC‑15 and 293T cell lines, and its effects on OSCC‑15 cell proliferation, invasion and apoptosis were assessed by performing a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay, Matrigel invasion and Annexin V‑FITC staining, respectively. In addition, a xenograft model was used to assess the effect of KAI1/CD82 on the in vivo growth of tumors. The overexpression of KAI1/CD82 inhibited the proliferation and invasion of OSCC-15 cells. It also enhanced the apoptotic rate of the OSCC‑15 cells. Furthermore, the overexpression of KAI1/CD82 inhibited tumor growth in the xenograft model. The results demonstrated that the overexpression of KAI1/CD82 significantly inhibited the proliferation and invasion of human oral cancer cells, and inhibited tumor growth in the xenograft model. Therefore, KAI1/CD82 may be considered as a potential therapeutic target in oral cancer.