A substrate treatment apparatus of the present invention includes: a spin base, on which a chuck member that holds the peripheral end of a substrate is disposed; a motor for rotating the spin base; aheater unit positioned between the substrate held by the chuck member, and the upper surface of the spin base; a treatment liquid supply unit that supplies a treatment liquid to the surface of the substrate held by the chuck member; and a microwave generation unit that generates microwaves toward the lower surface of the substrate from the heater unit. The microwave generation unit may include: amicrowave generation member including a waveguide disposed in the heater unit; a microwave oscillator that is provided outside of the heater unit; and a coaxial cable that connects the waveguide and the microwave oscillator to each other.