A scanning antenna includes a TFT substrate including a plurality of patch electrodes, a slot substrate including a slot electrode, and a liquid crystal layer provided between the TFT substrate and the slot substrate. The slot electrode includes a plurality of slots disposed corresponding to the plurality of patch electrodes and a solid portion not including the plurality of slot. When viewed from a normal direction of the substrate, the patch electrode is disposed across the slot in a first direction and overlaps the solid portion at both ends of the slot in each of a plurality of antenna units, and when viewed from the normal direction of the substrate, at least one of a periphery of the solid portion and a periphery of the patch electrode includes a recessed portion or a protruding portion in at least one antenna unit of the plurality of antenna units.