This kit is suitable for the total RNA of animals and plants with a template starting amount of 0.1-1 μg, as well as the separation and purification of small RNA. Connect the 3’and 5’ends of small RNA with universal adapters, and then go through the steps of reverse transcription, PCR amplification, and purification by PAGE gel or magnetic beads to finally obtain a sequencing library suitable for the Illumina® platform. The kit contains all the enzymes and buffers required for library construction. All components have undergone strict quality control and functional verification to ensure the stability and reproducibility of library construction to the greatest extent.