The increasing demand for the state-of-the-art transparent conductive electrodes has received great interest in synthesizing silver nanowires (AgNWs) with a uniform diameter that exhibit excellent conductance,transparency,flexibility and mechanical ductility.Herein,we report the controllable synthesis of ultrathin AgNWs with high aspect ratio via a polyol-assisted process.The diameter of AgNWs can be continuously modulated from 20 to 80 nm by simply adjusting the aging time.The self-assembled films fabricated by using AgNWs with a diameter of 20 nm as building blocks enable an excellent performance and show a sheet resistance of～30 Ω/sq and an optical transmittance of 94％.In addition,such nanowire-based conductive films can keep the excellent flexibility and resistance after bending 10,000 cycles.Similarly,the intelligent dimming films prepared by this AgNW films also have excellent flexibility and stability.