A distinct cultivar of Chrysanthemum plant named `Yonashville`, characterized by its upright, outwardly spreading and uniformly mounded plant habit; large plant size; good vigor; freely branching habit; uniform and early flowering; numerous daisy-type inflorescences that are about 7.3 cm in diameter; purple-colored ray florets with bright yellow-colored disc florets; and excellent postproduction longevity with inflorescences and leaves maintaining good substance and color for about four or five weeks in an interior environment.