For image fusion applications, the critical issue is how to produce a fused imagery with minimizing color distortion and maximizing the crease. However, due to nonsymmetrical spectral responses of IKONOS imagery, most existing techniques produce color distortion in 1m fused images. In our another report we have succeeded to reduce this color distortion significantly by using four spectral weighting parameters in our proposed fusion technique . However, block distortion appeared in part of the Im fused image. In this work we investigated the causes and proposed a sharpening process which uses Wavelet Transform to minimize this block distortion in 1m fused MS image. We have compared the 1m fused image before and after this sharpening process and found that the block distortion has almost been disappeared. Moreover, distortion of color of the entire image did not changed after this process.