Hydrogen peroxide (H₂O₂) is a crucial industrial chemical that plays an indispensable role in the advancement of human society. Electrochemical methods have recently emerged as one of the most appealing approaches for the green synthesis of H₂O₂; however, they necessitate highly efficient electrocatalysts. Herein, we report the design and successful fabrication of novel two-dimensional conductive metal–organic framework nanobelts (NBs), nickel pyrene 1,3,6,8-tetracarboxylate (Ni-PTC), composed of pyrene-1,3,6,8-tetracarboxylate (PTCA) as the organic linker and nickel as the metal node for highly efficient electrochemical H₂O₂ production. These Ni-PTC NBs possess abundant exposed active sites and accelerated electronic transfer, which boosts the H₂O₂ production with a rate of 11.96 mol·g⁻¹·h⁻¹ in a flow cell. An H₂O₂ solution with a concentration of 24.93 mmol·L⁻¹ is achieved at a current density of 50 mA·cm⁻². This work provides a promising approach for practical H₂O₂ electrosynthesis.