A washing machine includes a vibration damping device located in an outer casing for damping vibration of a tub using a cylinder enclosing an operating fluid including a functional fluid such as a magnetic viscous fluid changing a viscosity when an electrical energy is applied to the fluid. The vibration damping device includes the cylinder, a shaft inserted into the cylinder, a coil disposed in the cylinder, two yokes disposed between the cylinder and the shaft so as to be located at both axial sides of the coil respectively, the yokes forming a magnetic circuit together with the shaft and cylinder, a sealing member disposed axially outside one of the yokes in the cylinder to seal the operating fluid, and two bearings located axially outside the respective yokes in the cylinder to support the shaft so that the shaft is axially reciprocable.