A method of inspecting defects on an object includes irradiating predetermined particles with a laser beam to measure first scattered light intensities, irradiating plural types of defects with the laser beam to measure second scattered light intensities, determining types of some defects selected out of the plural types of defects using the first scattered light intensities, setting a discrimination line indicating a boundary value of the second scattered light intensities based on the determination, and discriminating, using the discrimination line, defects on the object.