To avoid agglomeration of ultrafine diamond particles and to improve machining precision of silicon (Si) wafers, a combination of gel casting and pore-forming agent is introduced to fabricate vitrified-bonded ultrafine diamond grinding wheel with ultrahigh porosity (~75%), honeycomb structure, and homogeneous microstructure. Moreover, the as-prepared grinding wheel possesses uniformly distributed closed pores, which are highly desirable for chip removal, heat dissipation and extended service life. In addition, influences of sintering schedules on microstructure, porosity and bending strength of the as-prepared grinding wheel are systematically investigated. Because of the honeycomb structure, the as-fabricated grinding wheel renders superior self-sharpness, which is required for continuous grinding of Si wafers without dressing, and this subsequently enhances the working efficiency. Results reveal that the surface roughness and damaged layer of the ground Si wafers are approximately 5.0 nm and 0.21 μm, respectively. The current study provides a novel pathway for efficiently processing high-quality silicon wafers.