Provided is a Low-E glass plate protection method capable of preventing or inhibiting alteration and erosion of Low-E layers. The protection method includes a step of applying a protective sheet to a surface of a Low-E glass plate having a Low-E layer comprising a tin component. Here, the Low-E layer comprises a tin component. The protective sheet has a PSA layer. The PSA layer comprises a phosphorus compound having a P—OR group. Here, R is a hydrogen atom or an organic group.

Provided is a Low-E glass plate protection method capable of preventing or inhibiting alteration and erosion of Low-E layers. The protection method includes a step of applying a protective sheet to a surface of a Low-E glass plate having a Low-E layer comprising a tin component. Here, the Low-E layer comprises a tin component. The protective sheet has a PSA layer. The PSA layer comprises a phosphorus compound having a POR group. Here, R is a hydrogen atom or an organic group.