IL-35 inhibited NK cell proliferation and function in vitro, reducing CD3-CD56+ cell proportion (F = 101.3, P < 0.0001), NKG2D expression (F = 49.29, P = 0.0002), and cytokine secretion (IFN-γ, F = 252.388, P = 0.000, Perforin, F = 39.372, P = 0.000, Granzyme, F = 1001.822, P = 0.000); Conditioned medium from IL-35-treated NK cells enhanced proliferation, invasion, and migration of NSCLC cell lines. This evidence concerns the gene KLRK1 and non-small cell lung carcinoma.