A pattern arrangement method of a semiconductor device is provided. In the pattern arrangement method, patterns are classified according to effective pitches and critical dimensions, and pattern dispersion is predicted according to the effective pitches and the critical dimensions by using a statistical analysis of process parameters. Two-dimensional coordinates of the effective pitches and the critical dimensions are constructed, and a dispersion map is made by arranging the predicted pattern dispersion on the corresponding coordinates. By arranging design patterns within a tolerance region of the dispersion map, the patterns satisfying the dispersion tolerance according to the significance of the layer and the design requirements can be arranged.