The very high-resolution satellite data from IKONOS and QuickBird are in a competition to aerial images today. Although the IKONOS satellite has provided the world's first source of commercially available high-resolution satellite imagery, QuickBird is currently the satellite with the highest resolution for civilian uses. While the IKONOS and QuickBird panchromatic band images with 0.82 and 0.61 meter respectively, provide intelligence quality imagery both for military applications, such as monitoring and assessment, as well as for civilian applications such as urban planning and mapping. The multi-spectral bands of IKONOS and QuickBird multi-spectral images with 3.28 and 2.44 meter respectively provide spectral-radiometric measurements for the many applications in land-use mapping, environmental monitoring and resource development. The successful launch of these two high-resolution satellites has narrowed the gap between satellite images and aerial photos. In the near future, it could even replace aerial photos for some applications depending on the resolution and accuracy requirements. In this study, the geometric accuracy analysis has been done with both QuickBird-2003and IKONOS-2002 images for Büyükçekmece region, Istanbul,Turkey. For the accuracy assessment, these two high-resolution images were rectified to UTM coordinate system using 1/5000-scaled orthophotos, GPS and, hand GPS coordinates. The results obtained were tested at the known points and effectiveness of the use of high-resolution data was outlined.