An automatic inspection method was proposed based on polynomial surface fitting and wavelet multi-scale. The influence of non-uniform background is successfully removed and Mura area was gotten. Related international organizations have drafted a standard on quantification Mura considering on area and contrast. Parameter of location was proposed according to the visual space of human eyes. We carried out some experiments on human factors, and got the relationship between the location of the Mura area and threshold of visual contrast. At last, 13 real TFT-LCD panel samples were evaluated with the proposed method, and the result is consistent with human intuition.