An antenna module includes a first antenna element disposed at a first dielectric substrate, a second antenna element disposed at a second dielectric substrate, a joint connecting the first dielectric substrate and the second dielectric substrate, and a power supply line. The second dielectric substrate is different from the first dielectric substrate with respect to the normal direction. The power supply line extends from the first dielectric substrate via the joint to the second antenna element and is configured to communicate a radio-frequency signal to the second antenna element. At least a part of the power supply line at the joint is formed in a direction crossing the polarization plane of radio waves radiated by the first antenna element and the second antenna element.