The inhibitory effects of kale juice on the growh and DNA incorporation of human cancer cells, using HT-29 colon cancer cells, MG-63 osteosarcoma cells, AGS gastric adenocarcinoma cells and K-562 leukemia cells, were studied. The growth of human cancer cells were inhibited in the presence of kale juice (10, 20 nd 40$mu$l/ml) and the effects were the juice concentration- and incubation time-dependent up to 6 days. When 20$mu$l/ml of kale juice was added to the media of HT-29, MG-63, AGS and K-562 cancer cells, the cell growth after 6 or 4 days of incubation was retarded by 83~95% of control group. Morphological changes of HT-29 colon cancer cells wre studied under inverted microscope. As the concentration of kale juice increased up to 20$mu$l/ml, degree of cell aggregation was decreased. Moreover, the DNA incorporation o AGS gastric adenocarcinoma cells and MG-63 osteosarcoma cells which were labeled with [$^3$H] thymidine was significantly reduced after 2 days of incubation at 37$^{circ}C$ with kale juice. Therefore, we concluded that kale juice strongly decreased the growth of various human cancer cells.