A method of forming a coating film includes horizontally supporting a substrate, supplying a coating solution to a central portion of the substrate and spreading the coating solution by a centrifugal force by rotating the substrate at a first rotational speed, decreasing a speed of the substrate from the first rotational speed toward a second rotational speed and rotating the substrate at the second rotational speed to make a surface of a liquid film of the coating solution even, supplying a gas to a surface of the substrate when the substrate is rotated at the second rotational speed to reduce fluidity of the coating solution, and drying the surface of the substrate by rotating the substrate at a third rotational speed faster than the second rotational speed.