Antenna substrate, antenna device, and electronic component

An antenna substrate comprising:

• a substrate body;
• a ground layer formed of a conductor and located on a surface of the substrate body;
• and
• a radiation element formed of a conductor and located on the surface of the substrate body and spaced from the ground layer on one side in a first direction, wherein
• the ground layer includes a first portion and a second portion that are arranged in a second direction orthogonal to the first direction, the first portion and the second portion being separated by a boundary being a portion of the ground layer that has overlap with a virtual straight line passing through a center of the radiation element in the second direction and extending in the first direction,
• the first portion is located on one side in the second direction with respect to the boundary,
• the second portion is located on the other side in the second direction with respect to the boundary,
• the first portion includes an outer edge portion that is a part of an outer edge of the first portion, is located on the one side in the first direction, and partially extends along the second direction,
• the outer edge portion includes a first edge and a second edge, and
• the second edge is located on the one side in the second direction with respect to the first edge and is located on the other side in the first direction with respect to the first edge.