The invention relates to a method for amplifying natural killer cells and natural killer T cells in vitro, which is cultured at an initial cell density of 0.5×10 6 to 5×10 6 cells/mL, and the cell density is adjusted again at a specific time after culture. 0.5x10 6 ~ 5x10 6 cells / mL, in order to maintain a better cell growth environment, thereby increasing the amplification efficiency of the cells, according to which the method of the present invention can be used in a shorter time than the prior art. The total number of cells was obtained, and the cell survival rate and the ratio of NK/NKT cells were high, and the proportion of NK/NKT cells with cytotoxicity was also high in the activated state.本發明係關於一種體外擴增自然殺手細胞及自然殺手T細胞之方法，該方法係以0.5x106~5x106cells/mL之初始細胞密度進行培養，並於培養後特定時間點將細胞密度再次調整為0.5x106~5x106cells/mL，藉以維持較佳之細胞生長環境，進而提升細胞之擴增效率，據此，本發明之方法，相較於習知技術而言，得以於較短的時間獲得較多之細胞總數，且細胞存活率以及NK/NKT細胞比例皆較高，處於活化態而具備細胞毒殺性之NK/NKT細胞比例亦較高。
