Abstract: To study the effect of EMS treatment with different concentrations of chemical mutagens on the germination of dry and sand stored lilium seeds, and to screen the suitable mutagenic concentration and mutagenic time. The self-crossing seeds of Lilium regale Wilson were mutagenic treated with chemical mutagenic agent EMS. Three treatment times（2 hours, 4 hours, 8 hours） and four EMS concentrations（0, 0.4%, 0.8%, 1.2%） were set for the self-crossing seeds of Lilium regale Wilson. The results showed that the relative survival rate of dried seeds was 65.38% at 0.4% and nearly half lethal dose at 4 hours, while the relative survival rate of seeds treated with sand storage was 62.3% at 0.4% and nearly half lethal dose at 2 hours. Therefore, 4 hours of 0.4% EMS treatment was the appropriate way to treat dried lily seeds, and 2 hours of 0.4% EMS treatment was the appropriate way to treat sand seed.