Bamboo　powder　and　its　dissolution　process　in　ionic　liquids　were　analyzed　according　to　Fourier　Transform　Infrared　Spectroscopy　(FT-IR)　coupled　with　two-dimensional　correlation　spectroscopy　and　chemometrics.　Second　derivative　spectroscopy　was　applied　to　enhance　the　spectra　resolution,　obtaining　more　molecular　vibration　information.　After　executing　the　principal　component　analysis　(PCA)　on　ATR-FTIR　spectra　of　undissolved　bamboo　powder　residue,　we　obtained　a　three-staged　dissolution　process　model.　In　addition,　the　conclusion　that　cellulose/hemicellulose　dissolving　prior　to　lignin　was　summarized　through　the　PCA　loading　spectrum.　Point-line　moving　window　two　dimensional　correlation　spectroscopy　(PL-MW2DCOS)　furtherly　unveiled　the　dissolution　details.　This　work　provided　us　a　clear　dissolution　process　of　biomass　using　a　rapid,　label-free　and　easy-operation　method.　(C)　2018　Elsevier　B.V.　All　rights　reserved.