The invention provides a gas diffusion layer for a fuel cell on which a microporous layer is disposed, which can have lower contact resistance with electrode catalyst layers and improved gas diffusion performance. The gas diffusion layer for a fuel cell of the disclosure has a conductive porous substrate layer and a microporous layer laminated in that order, wherein the microporous layer comprises carbon particles and a water-repellent resin, and has an impregnating portion that impregnates the conductive porous substrate layer and a non-impregnating portion that does not impregnate the conductive porous substrate layer, the thickness of the non-impregnating portion is greater than 0.0 μm and 20.0 μm or smaller, and the thickness of the impregnating portion is 29% or lower with respect to the total thickness of the microporous layer.