Electrochromic　film　was　fabricated　with　a　tungstic　oxide　target　by　the　RF　reactive　magnetron　process.　Orthogonal　test　method　was　used　to　optimize　process　parameters　and　then　to　design　excellent　performance　Electrochromic　film.　Heat　treatment　process　was　adopted　to　improve　the　endurance　of　electrochromic　performance.　Results　showed　that　Electrochromic　properties　improved　Significant.　Variation　of　the　transmittance　(AT)　can　reach　89.3%　in　the　preparation　condition　of　w(O)=60%,　p=2.5　Pa　and　P=145　w.　Coloring　rate　increased　slightly　while,　duration　of　Electrochromic　state　and　ion　storage　capacity　can　extend　to　32　h　and　3.96　mC/cm　2,　respectively;　simultaneously,　cycling　stability,　crystallization,　density　and　electrochromic　response　time　were　ameliorated　under　justifiable　heat　treatment　process.