The present invention relates to a method for preparing a slurry composition and a slurry composition prepared thereby, and has advantages of reducing scratches and residual particles, which are considered to be one of the biggest factors contributing to the decline in yield due to macroparticles and aggregated particles, while maintaining a high polishing rate, in a semiconductor CMP process. Furthermore, the present invention can achieve excellent results in the application to various patterns required in the ultra-large scale integration semiconductor process, the wafer non-uniformity (WIWNU) exhibiting a polishing rate, polishing selectivity, and polishing uniformity, which meet the needs, and the micro-scratch minimization.