Image interpolation is an estimation method on value of non-allocated pixel coordinate in the process of image scaling, which has been researched for subjective and objective enhancement of interpolation performance. In this paper, we propose improved image interpolation using SDR(self degradation restoration). The proposed method uses SDR to estimate loss pixel value on image scaling, and combines the estimated loss information and interpolated image to generate more enhanced result image than interpolated image itself. The proposed method can be applied to each interpolation function, and PSNR increases maximum value by 1.5dB through these experiments. The proposed method can be used as the technique which can be replaced with image interpolation function.