A sheet for protecting a paint film is disclosed, which does not cause deterioration or discoloration the paint film even when the sheet is adhered to protect the paint film under the condition containing water or water vapor over a long period of time and thus can maintain the adhered state without peeled off the sheet. The sheet for protecting a paint film comprises a multi-layer substrate comprising a water or water vapor barrier layer as a surface layer and a water or water vapor-permeable layer as a back, and a pressure-sensitive adhesive layer formed on the water or water vapor-permeable layer.