Provided is an electrochromic device including: two substrates opposed to each other; an electrode and a conductive reflection layer interposed between the two substrates; a first electrochromic coating layer interposed between the electrode and the conductive reflection layer; and an electrolyte layer interposed between the first electrochromic coating layer and the conductive reflection layer, whereby uniform discoloration and decolorization can be performed, the efficiency of power consumption can be enhanced, and a durability of the device and the speed of a decolorization reaction can be improved.