Abstract: A screen apparatus for separating a foreign material from a papermaking material includes a tank for receiving the papermaking material; a screen dividing the tank into a primary chamber and a secondary chamber, a papermaking material supply passage for supplying the papermaking material into the tank, a foreign material discharge passage for discharging the foreign material in the papermaking material, a papermaking material discharge passage for discharging the papermaking material passing through the screen, a foil disposed in the primary chamber for stirring the papermaking material, and a dilute water introducing passage for introducing dilute water into the primary chamber. The dilute water introducing passage has a tip end tilted toward a rotational center of the foil in a direction that the foil rotates. The dilute water introducing passage has a tip opening section at the tip end facing a side of the foil.