In　view　of　the　biological　significance　and　micro-heterogeneity　of　protein　glycosylation　for　human　health,　specific　enrichment　of　N-glycosylated　proteins/peptides　from　complex　biological　samples　is　a　prerequisite　for　the　discovery　of　disease　biomarkers　and　clinical　diagnosis.　In　this　work,　we　propose　a　＂grafting-from＂　N-glycoprotein　enriching　method　based　on　the　in-situ　growth　of　thermoresponsive　polymer　brushes　from　the　N-glycosylated　site　of　proteins.　The　initiator　was　first　attached　to　the　pre-oxidized　glycan　moieties　by　hydrazide　chemistry,　from　which　the　thermoresponsive　polymers　can　be　grown　to　form　giant　protein-polymer　conjugates　(PPC).　The　thermosensitive　PPC　can　be　precipitated　and　separated　by　raising　the　temperature　to　above　its　lower　critical　solubility　temperature　(LCST).　Mass　spectrometry　verified　210　N-glycopeptides　corresponding　to　136　N-glycoproteins　in　the　rabbit　serum.　These　results　demonstrate　the　capability　of　the　tandem　thermoprecipitation　strategy　to　enrich　and　separate　N-glycoprotein/glycopeptide.　Due　to　its　simplicity　and　efficiency　specifically,　this　method　holds　the　potential　for　identifying　biomarkers　from　biological　samples　in　N-glycoproteome　analysis.