The invention discloses a method for detecting tumor killing activity of NK (Natural Killer) cells. The method for detecting the tumor killing activity of the NK cells comprises the following steps: recovering and culturing K562 cells; preparing a target
cell K562; preparing
effector cells NK; the K562
cell suspension and the NK
cell suspension are mixed according to the effect-target ratio to serve as an experimental group, the K562 cell suspension serves as a control group, after the experimental group and the control group are incubated in an
incubator for a period of time, the cells are transferred into a centrifugal tube and cleaned with PBS, then PI dye liquor is added for incubation, and the cell suspension is obtained. Detecting the
apoptosis rate of the K562 cells in the experimental group and the control group by adopting a flow cytometer, and calculating the tumor
killing rate of the NK cells; the killing activity of the NK cells to the K562
tumor cells is evaluated through a CFSE / PI labeling method, operation is relatively simple, consumed time is short, sensitivity is high,
repeatability is good, and the method has the advantages of being safe, efficient, economical, stable and the like and has good application value.