The invention discloses a well-flushing step-by-step unsetting packer, which comprises an upper joint, a well flushing cylinder tube, a rubber tube shaft, a rubber tube, a center pipe, a locking device, a main piston, a connecting sleeve and a lower joint. The well-flushing step-by-step unsetting packer has the advantages that (1) an inlet of a well-flushing passage is of a structure with a plurality of slender seams, so that the flow-passing area of the passage is sufficiently large, large-particle solid phase impurities can be prevented from entering the well-flushing step-by-step unsetting packer to block an inner passage, and the smoothness of a tool inner cavity well-flushing passage is ensured; (2) the well-flushing passage of the packer adopts a streamline design, so that machine impurities and solid phase particles can easily flow out, and passage blockage due to accumulation cannot easily occur; and (3) a step-by-step unsetting mechanism is arranged inside the packer, so that during the multi-stage use, an upper-stage packer is firstly unset; then, a lower-stage packer is unset; the unsetting force is not accumulated during the unsetting; and the packer is enabled to be easily unset.