Provided is a PSA sheet that can be processed with excellent precision while providing excellent light-blocking properties in an in-plane direction and in the thickness direction in an embodiment where the support substrate has a limited thickness. The PSA sheet has a support substrate having a thickness less than 75 μm and a PSA layer placed at least on one face of the support substrate. The PSA sheet has light transmittances of 0.04% or lower in XY and Z directions thereof.