Shape-Adaptive Polishing (SAP) is an effective method for the polishing of hard and brittle materials. The work aims to verify the feasibility of the adaptive grinding and polishing of 3D-printed nickel-based superalloy engine blades with elastic matrix abrasive tools. Firstly, a finite element model of the elastic contact between the polishing tool and the blade was established based on the elastic grinding and polishing techniques with silicon rubber-based abrasive tools. In addition, the stress distribution and material removal function within the contact area were analyzed. Furthermore, the effect of contact deformation and material removal of abrasive tools on trajectory planning was studied according to the finite element analysis. Finally, the reasonable trajectory step size and spacing were determined, where the contact state between the grinding tool and the workpiece was kept unchanged during the grinding and polishing process. The experimental tests were carried out on a desktop CNC machining system. EOSM290 3D printer was employed to fabricate the blade, and the GH4169 nickel-based alloy was selected as the source material. The preparation of the abrasive tool was realized by a molding process, where the Smooth-On Ecoflex 0050 silicon rubber and micron-sized diamond grains were selected as the binder matrix material and abrasives. During the experiment, the rotation axis of the silicon rubber-based abrasive tool was consistently vertical to the blade surface by controlling the position and orientation of the blade. The simulation results showed the elliptical contact area between the elastic tool and the curved surface workpiece. Also, the stress distribution and material removal rate decreased gradually from the ellipse‘s center to the periphery. The optimal track spacing determined was 9 mm when the compression of the elastic abrasive tool was 3 mm. The optimal track spacing increased with the increasing compression of the elastic abrasive tool. The polished blade surface topography was observed through the optical microscope. The experimental results showed that the blade surface had no noticeable scratches and dents after polished with the adaptive polishing tool and planned trajectory. The reason was that the elastic matrix abrasive tool had excellent flexibility in the polishing process and deformed with the blade surface according to the shape, thereby achieving flexible adaptive and uniform polishing under the condition of ensuring the stability of polishing parameters. A group of 10 sample points was taken in the polishing area of the blade surface for measuring the surface roughness by Mitutoyo SURFTEST SJ-310 roughness meter. The surface roughness value was reduced from 1.846 μm to 0.182 μm, and the standard deviation was decreased from 0.108 μm to 0.026 μm. The blade weight loss before and after polishing was measured by an electronic balance, and the material removal rate was calculated as 3.432×109 μm3/min. In summary, the silicon rubber-based abrasive tool can realize the precision polishing of GH4169 nickel-based alloy blades. The adaptive trajectory planning based on the stress distribution in the contact area of the elastic abrasive tool and the transformation of the workpiece position and orientation is promising to improve the consistency of the surface quality in the blade polishing area.