A wideband antenna includes a grounding element; a feed-in terminal; a first radiating unit, electrically connected to the feed-in terminal and extending from the feed-in terminal toward a first direction; a second radiating unit, electrically connected to the feed-in terminal, extending from the feed-in terminal toward a second direction, and including a meander-shaped element; and a third radiating unit, electrically connected to the grounding element, extending from the grounding element toward the first radiating unit and the second radiating unit, and having one segment parallel to the meander-shaped element, for coupling the meander-shaped element.