A thin film transistor, an array substrate and a display device are provided. The thin film transistor is on a base substrate and includes a gate electrode, a first electrode, and a second electrode on the base substrate. The gate electrode includes a first body portion and a first extension portion extending along the first direction, electrically connected with the first body portion, and spaced apart from the first body portion by a first spacing. The first electrode includes a first overlapping end, an orthographic projection of the first overlapping end on the base substrate at least partially overlaps with an orthographic projection of the first body portion on the base substrate; a first compensation end at a side of the first overlapping end away from the first body portion, an orthographic projection of the first compensation end on the base substrate at least partially overlaps with an orthographic projection of the first extension portion on the base substrate; and a first intermediate portion connecting the first overlapping end and the first compensation end, an orthographic projection of the first intermediate portion on the base substrate is within an orthographic projection of the first spacing on the base substrate.