An antenna module includes a dielectric substrate, a radiation electrode, a ground electrode, and a current-interrupting element. The radiation electrode is disposed in a layer of the dielectric substrate, and the ground electrode is disposed in another layer of the dielectric substrate. The current-interrupting element is electrically connected to the ground electrode. The current-interrupting element is configured to interrupt a current flowing through the ground electrode. The current-interrupting element has a first edge portion electrically connected to the ground electrode and a second edge portion left open and includes a planar electrode parallel to the ground electrode. The dimension of the current-interrupting element in the direction from the first edge portion to the second edge portion is about λ/4, where λ is the wavelength of a radio-frequency signal radiated from the radiation electrode.