In a manufacturing method of a semiconductor device according to one embodiment, a first gas containing a first metal element is introduced into a chamber having a substrate housed therein. Next, the first gas is discharged from the chamber using a purge gas. Subsequently, a second gas reducing the first gas is introduced into the chamber. Next, the second gas is discharged from the chamber using the purge gas. Further, a third gas different from the first gas, the second gas, and the purge gas is introduced into the chamber at least either at a time of discharging the first gas or at a time of discharging the second gas.