The　evolution　of　surface　morphology　of　Cu-W　thin　films　with　deposition　time　on　silicon　wafers　was　studied　by　discrete　wavelet　transform　(DWT).　A　strategy　based　on　wavelet　transform　to　describe　surface　morphology　of　thin　films　was　presented.　The　results　showed　that　the　surface　morphology　of　thin　films　was　unstable　until　the　sputtering　time　exceeds　10　min.　The　surface　morphology　variations　of　different　thin　films　could　be　distinguished　primarily　by　high　frequency　signals.