An array substrate, a method for manufacturing an array substrate and a display device are provided. The array substrate includes: a base substrate, and an insulating layer, a gate line, a source electrode, a drain electrode, and a data line on the base substrate. The insulating layer includes a light transmission portion and a light shielding portion, and orthographic projections of the gate line, the source electrode, the drain electrode, and the data line on the base substrate are all within an orthographic projection of the light shielding portion on the base substrate.