Cervical cancer is a major cause of cancer mortality in women worldwide and is an important public health problem for adult women in developing countries. Despite aggressive treatment with surgery and chemoradiation, the outcomes for cervical cancer patients remain poor. In this study, the antitumor activity of cytokine-induced killer (CIK) cells against human cervical cancer was evaluated in vitro and in vivo. Human peripheral blood mononuclear cells were cultured with IL-2-containing medium in anti-CD3 antibody-coated flasks for 5 days, followed by incubation in IL-2-containing medium for 9 days. The resulting populations of CIK cells comprised 95% CD3(+), 3% CD3(-)CD56(+), 35% CD3(+)CD56(+), 11% CD4(+), <1% CD4(+)CD56(+), 80% CD8(+), and 25% CD8(+)CD56(+). At an effector-target cell ratio of 100:1, CIK cells destroyed 56% of KB-3-1 human cervical cancer cells, as measured by the (51)Cr-release assay. In addition, CIK cells at doses of 3 and 10 million cells per mouse inhibited 34% and 57% of KB-3-1 tumor growth in nude mouse xenograft assays, respectively. This study suggests that CIK cells may be used as an adoptive immunotherapy for cervical cancer patients.