Abstract: Providing a method for improving the germination of plant seeds for use in agriculture, gardening and tree planting on mountains and in forests, where the germination of the seeds is suppressed physically or physiologically due to the hard seed coat (testa or pericarp or the like) as the structures surrounding seed embryos, by secure and uniform treatment of each seed without any damage of seed embryo to produce seeds with improved germination in a stable manner without any loss and without creating problems in the working environment, and providing germination improved seeds. Germination is improved by allowing laser beam to irradiate a part of the seed coat of a plant seed to perforate a part of the seed coat to thereby overcome physical or physiological factors causing the suppression of germination, such as gas permeability and water permeability to seed embryo.