This product is a serum-free CIK cell culture medium with defined composition and free of animal-derived components. It is specifically optimized for the efficient induction, large-scale expansion, and functional maintenance of cytokine-induced killer cells. Its core formulation precisely mimics the human immune activation microenvironment by integrating high concentrations of key cytokines such as IL-2 and IFN-γ, along with unique metabolic pathway regulatory components. This enables efficient promotion of directed differentiation and clonal expansion of peripheral blood mononuclear cells into CIK cells, while significantly enhancing their functional capacity. IFN-γ, and unique metabolic pathway regulatory components. This formulation efficiently promotes the directed differentiation and clonal expansion of peripheral blood mononuclear cells into CIK cells, significantly enhancing the proportion of CD3⁺CD56⁺ double-positive effector cells and their granzyme B-mediated broad-spectrum tumor killing activity. It ensures sustained high cell viability, phenotypic stability, and persistent killing function throughout the in vitro culture cycle.