An apparatus for applying a coating solution to a surface of a substrate to form a coating film of desired thickness thereon. The apparatus includes a rotary supporting device for supporting and spinning the substrate in horizontal posture, a solvent spraying device for spraying a solvent to the substrate, a coating solution supplying device for supplying the coating solution to the substrate, a storage device for storing a processing program stipulating varied points and periods of time, a timer acting as a reference for each point or period of time stored in the storage, and a controller operable to perform controls based on the points and periods of time and with reference to the timer.