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The achievement of low-resistance connection in REB2C3O7-z (REBCO, RE = Y, Gd) coated conductors (CCs) has become one of the strategic factors for magnet applications. In this letter, we fabricated low-resistivity (Rsj = 4.9 nΩ·cm2) Ag-diffusion joints of REBCO CC by improving the interface connection of the Ag stabilizer. The effective contact area at the interface between two Ag stabilizers can be increased by polishing the surface of the Ag stabilizers, which can reduce joint resistance (Rj). Compared with a traditional diffusion temperature (400 °C), diffusion bonding of the Ag stabilizers at higher temperatures (800 or 850 °C, typical connection temperatures for superconducting joint) can promote interface connection between two Ag stabilizers. The oxygen content in REBCO will be reduced due to diffusion bonding at higher temperatures. Therefore, we etched some microchannels that serve as the fast oxygen diffusion paths on the surface of the Ag stabilizers to help restore the oxygen content, thereby recovering critical current (Ic) and reducing Rj. The connection mechanism of the interface between two Ag stabilizers was investigated through the cross-sectional analysis and delamination of the joint part. In addition, the REBCO layer can be completely peeled off and almost retain the original Ic by diffusion bonding of the Ag stabilizers at higher temperatures. This fabrication technique is a unique practicable solution to reduce the Rj for the CC with thin Ag stabilizers and improve the peeling quality of the REBCO layer for efficiently fabricating the superconducting joint. [ABSTRACT FROM AUTHOR]