The invention discloses a multistage anchoring type resin anchor rod and an anchoring method of the multistage anchoring type resin anchor rod. The multistage anchoring type resin anchor rod comprises an anchor rod body and an orifice pretensioner. Point anchoring sections are arranged on the anchor rod at intervals. Other sections are free sections. According to the point anchoring sections, tooth-shaped annular cutters are machined at the positions, provided with the point anchoring sections, of the anchor rod body. The tooth-shaped annular cutters are sleeved with two-component anchoring resin cartridges. The two ends of each two-component anchoring resin cartridge are sleeved with isolation gaskets. Accordingly, the anchor rod body is sequentially divided into the first free section, the first point anchoring section, the second free section, the second point anchoring section, the third free section and the third point anchoring section from an orifice, and it is required that the first free section is located in a surrounding rock loose area, the third point anchoring section is located in a surrounding rock elastic area, and other sections are located in a surrounding rod plastic area. The number of the point anchoring sections, the number of the free sections and the lengths of all the sections can be adjusted according to the surrounding rock pressure distribution characteristics, loads are dispersed, ultra-strong stress concentration is prevented from happening to the ends of the anchor rod, and the anchor rod body is prevented from breaking or being pulled out.