The invention relates to an RNA (Ribonucleic Acid) antisense purification method. The RNA antisense purification method comprises the following steps: S1, cross linking and pyrolysis of cells and digestion of genome DNA (Deoxyribonucleic Acid), thus obtaining an RNA sample; S2, preparation of a probe group solution; S3, pre-treatment of magnetic beads; S4, preparation of a probe group-magnetic bead compound; S5, antisense purification; S6, elution of RNA; S7, purification of the RNA. According to the RNA antisense purification method disclosed by the invention, the magnetic beads are sealed by using BSA (Bull Serum Albumin) and random oligonucleotide primer in advance, so that non-specific adsorption of the magnetic beads is reduced; the magnetic beads are in incubation with probes at first and then is in incubation with the RNA after residual probes are removed, non-specific combination of streptavidin with protein, nucleic acid and the like is sealed by excessive probes, the detection specificity is increased, and the sensitivity is high; multiple washing under a gradient temperature is carried out after hybridization, so that the magnetic beads are enabled to be fully combined with the probes and to be combined with a target RNA, and the hybridization efficiency is increased.