In this paper, irregular sub-micron flaky silver has been rapidly synthesized at room temperature. The product was detailedly characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and ultraviolet visible (UV-Vis) spectroscopy. The average diameter and thickness of the irregular sub-micron flaky silver were 200-600 nm and similar to 70 nm, respectively, and the flake-particle ratio of product was over 95%. Further, the possible formation mechanism of the irregular sub-micron silver flakes was discussed. The conductive pastes doped with irregular sub-micron flaky silver revealed a good conductivity of 3.1 x 10(-4) Omega.m, indicating its potential applications in the electronic materials.