A novel approach for the preparation of a well-ordered nanosieve structure of silver nanoparticles using a Ag-1,2-benzenedicarboxylate (Ag-1,2-BDC) complex and sodium stearate under a hydrothermal process was performed. The X-ray diffraction (XRD) pattern suggests the formation and crystallinity of silver nanoparticles. The average particle size of silver nanoparticles was 35 nm and shows a hexagonal shape with a nanosieve structure as confirmed by transmission electron microscopy (TEM). The selective area electron diffraction (SAED) pattern of the nanosieve suggests a mono-crystalline nature of the silver nanoparticles. The SEM image reveals that the particles are of spherical and granular nature. The UV-Vis absorption spectrum shows a characteristic absorption peak of silver nanoparticles at 410 nm. The findings suggest that hydrothermal induced assembly should be a convenient and effective route for the preparation of new silver nanostructures. In addition, the Ag nanosieve modified electrode (AgNS/GC) exhibited an excellent electrocatalytic activity toward the reduction of hydrogen peroxide (H₂O₂). This silver nanosieve may also be a promising candidate for electronics and photonics application.