A film forming method comprises loading a substrate on a rotary table, forming an adsorption region for adsorbing a raw material gas to the substrate by discharging the raw material gas from multiple discharge ports, forming a reaction region, to which a reaction gas is supplied, at a position spaced from the adsorption region, separating an atmosphere of the adsorption region and an atmosphere of the reaction region by exhausting and by supplying a purge gas, forming a film by performing a cycle a plurality of times to deposit the reaction product on the substrate, the cycle comprising passing the substrate through the adsorption region and the reaction region and setting a combination of flow rates of the raw material gas for a first pattern in order to perform the cycle with the first pattern and for a second pattern in order to perform the cycle with the second pattern.