The present study was conducted to investigate the effects of stem extracts from perilla and buckwheat on the germination and seedling growth of barnyard grass and chinese cabbage. The major results obtained are as follows. The stem extracts showed inhibiting effects on seed germination. The degree of inhibition was much higher with the extracts of perilla than those of buckwheat and more sensitive to chinese cabbage than barnyard grass. The trends of inhibition effects on seedling growth were the same as in the seed germination with lower degree. The roots were more sensitive to the extracts than the tops with higher degree with buckwheat extracts.