Abstract: This study was carried out to evaluate the inhibitory effects of 70% methanol extracts from dwarf lilyturf (Ophiopogon japonicus K.) roots on two isolates (MAFF305480和MAFF101002) of rice blast fungus (Magnaporthegrisea) from Japan and rice blast disease at seedling stage. The results indicated all extracts from dwarf lilyturf (Ophiopogon japonicus K.) roots with 1/10，1/20，1/40 and 1/80 original solution significantly inhibited both the mycelial growth of the two isolates(MAFF305480 and MAFF101002) by over 56.4% and the degrees of rice blast disease, induced by inoculation of the two isolates, in rice seedlings by over 38.4% and their inhibitory effects become strong along with the higher concentration, which suggest that the extracts from the dwarf lilyturf roots contained inhibitory chemicals for growth of rice blast fungus and even directly inhibited the occurrence and development of rice blast disease in rice seedlings.