Triangular silver nanoplates with its border size of 100±10nm and thickness of 30nm were synthesized by a chemical method. These triangular silver nanoplates were characterized by TEM, UVVis spectroscopy and xrays diffraction analysis. Results obtained showed that these triangular silver nanoplates are perfect with sharp corners and selfassembled into twodimensional ordered monolayer on the carboncovered copper grid due to the adsorption of organic molecules in between these silver nanoplates. The wellaligned silver film on Si (100) substrate showed strong surfaceenhanced Raman scattering for pyridine molecules.