The waviness on cold rolled sheet was measured and calculated by following three methods: high pass Gaussian filter with low pass Gaussian filter, high pass exponent filter with low pass exponent filter and polynomial filter with low pass Gaussian filter. The effect of filtering techniques and measuring length on the results of waviness parameter was analyzed. It indicates that application of high pass Gaussian filter with low pass Gaussian filter leads to higher and unstable results. Moreover,the waviness parameter based on the methods of high pass exponent filter with low pass exponent filter and polynomial filter with low pass Gaussian filter is stable on measuring length.