A low-pressure abrasive flow polishing (LAFP) technology is presented to address the issue of fabricating rectangular microgroove of Cu and SUS304 materials. The effects of abrasive flow on the polishing efficiency and uniformity are analyzed numerically and experimentally. The rectangular structure of polishing microchannel is designed and optimized by simulating the trajectory and erosion action of particles using computational fluid dynamics (CFD) model. The distributions of turbulence intensity and shear force in the polishing microchannel are analyzed. Polishing experiments are conducted to fabricate microgrooves on Cu and SUS304 materials. The experimental results reveal the increase of material removal with the increase in particle size, polishing pressure, and particle concentration. Surface roughness of Ra 4.8 nm and Ra 12.7 nm are respectively obtained when polishing the rectangular microgroove of Cu and SUS304 materials. Simulation and experimental results show that LAFP using polishing microchannel can fabricate microstructures with high-quality surface. (C) 2017 Elsevier B.V. All rights reserved.