A protection mechanism for a working vehicle includes a roof above an operator's seat and including a cutout extending along a top-bottom direction, and an electric device at least partially located in the cutout. The cutout has a dimension along a vehicle-body-width direction that is uniform or substantially uniform along a front-to-rear direction or increases in the front-to-rear direction. The cutout has a thickness along the top-bottom direction that decreases in the front-to-rear direction. The roof include, in an upper surface thereof, a first groove located on an opposite side of the cutout from the electric device and extending in a direction away from the cutout.