Disclosed is a device for polishing an intraocular lens by using an electrorheological effect. The device comprises a supporting plate (14), an electric motor (16), a conductive slip ring (18), an outer sleeve (20), a tool shaft (22), a connecting flange (24), an annular electrode (26) and a tool needle (28). The electric motor (16), an outer ring of the conductive slip ring (18), and the outer sleeve (20) are all installed on the supporting plate (14). The electric motor (16) drives the tool shaft (22) to rotate by means of a transmission assembly. One end of the tool shaft (22) is closely fitted with an inner ring of the conductive slip ring (18), and the other end of the tool shaft extends into the outer sleeve (20). The connecting flange (24) is installed on the outer sleeve (20). The annular electrode (26) is connected to the connecting flange (24). One end of the tool needle (28) is connected to the tool shaft (22), and the other end of the tool needle extends out of the annular electrode (26). The tool needle is used as a cathode and the annular electrode is used as an anode in the apparatus. The apparatus thus has a good insulation effect and both tool needle and annular electrode can be detached and adjusted, such that different polishing requirements can be met, and high-quality deterministic polishing for an aspherical intraocular lens can be completed. Further the present invention provides a method for polishing an intraocular lens by using an electrorheological effect.