A simple method for the synthesis of silver nanowires (NW) in ethylene glycol is presented here with its diameter controlled by addition of chloride ions. The synthetic process consists of two separating steps, i.e., nucleation and growth. The resulting diameter, between 100 and 55 nm, becomes smaller when more chloride ions are added in the second step. Different silver nanowires are then coated on the glass substrate to fabricate transparent electrodes. A sheet resistance of 10 Omega/sq with optical transmittance of 80% can be obtained.