The kit is a ready-to-use reagent for the isolation of total RNA from plant tissue with polysaccharide and polyphenol. Add Lysis to the processed sample and transfer the mixture to a centrifuge column, and then total RNA can be easily isolated through several washing and elution steps. The kit provides a very simple, fast and inexpensive technique to isolate high quality RNA and can be high throughput. Pure RNA can be widely applied in northern blotting, blotting hybridization, poly(A)+ selection, in vitro translation, RNase protection assay, RT-PCR/real-time RT-PCR analysis, cDNA library construction, etc.