A method for fabricating an electrochromic device includes: depositing a first transparent film on a first substrate; depositing a first mesh structure on the first transparent film; depositing a second transparent film on the first mesh structure; depositing an electrochromic layer of WO3 or MoO3 on the second transparent film by an arc-plasma process to form a first electrode structure; depositing a third transparent film on a second substrate; depositing a second mesh structure on the third transparent film; depositing a fourth transparent film on the second mesh structure; forming an ion storage layer of PB on the fourth transparent film to produce a second electrode structure; binding the first and second electrode structures by having the electrochromic layer to face the ion storage layer; and, forming an electrolyte layer between the first and second electrode structures to produce the electrochromic device. In addition, an electrochromic device is also provided.