A biodegradable, disposable absorbent article, such as a diaper, having a non-woven inner layer of natural fibers and a non-woven outer layer of natural fibers and a treatment applied to at least one surface thereof. The treatment includes at least one compound selected from the group consisting of waxes, urethanes, silicones, fluorocarbons, and non-fluorochemical repellants. The absorbent article has a core of natural fibers or fibrous material, and optionally polyacrylate superabsorbent particles, positioned between the inner layer and the outer layer. The article may contain polylactic acid films between the layers.