A substrate processing method includes a first process (step S12 to step S16) of forming a first resist pattern by exposing a substrate having thereon a first resist film to lights, developing the exposed substrate and cleaning the developed substrate; and a second process (step S17 to step S20) of forming a second resist pattern by forming a second resist film on the substrate having thereon the first resist pattern, exposing the substrate having thereon the second resist film to lights, and developing the exposed substrate. A first processing condition is determined based on first data showing a relationship between a first processing condition under which a cleaning process is performed on the substrate in the first process (step S16) and a line width of the second resist pattern, and the first process (step S16) is performed on the substrate under the determined first processing condition.