Considering the LCD-Mura defect background reconstructed by current background suppression methods was vulnerable to introduced noise and target defects, a kind of defect image background modeling method based on Singular Value Decomposition (SVD) and maximum entropy was proposed. The singular value sequence was obtained by the SVD of the image pixel matrix. The correspondence between the image components and the singular values was derived by the matrix norm, and the entropy of each component of the image was calculated by the ratio of each component singular value, then effective singular values of background reconstruction was determined by the maximum entropy. Finally, the background was got by the matrix reconstruction, and the general method of evaluating the effect of background reconstruction was put forward. Compared with the three B spline curve fitting methods, the proposed method can improve the contrast of region Mura by 0.59 times at least and the line Mura contrast by 7.71 times at most; and compared with the Discrete Cosine Transform (DCT) method, it reduces the noise of the point Mura by 33.8 percent at least and the line Mura noise by 76.76 percent. The simulation results show that, the model has the advantages of low noise, low loss and high brightness, and can be used to construct the background information of the defect image more accurate.