The present invention relates to a method for producing natural killer cells using T cells, and more particularly, to a method for producing natural killer cells, which comprises culturing seed cells using CD4(+) T cells as feeder cells. The method for producing natural killer cells using T cells according to the present invention is a method capable of producing natural killer cells by selectively proliferating only natural killer cells from a small amount of seed cells while maintaining the high killing activity of the natural killer cells. The method of the present invention can produce a large amount of natural killer cells that can be frozen, and thus is useful for commercialization of cell therapeutic agents.
