A rear discharge type mower apparatus includes: a blade housing having a top plate, a front wall and at least one side wall and a first front guide plate and a second front guide plate. Each of the first and second front guide plates are located rearwardly of the front wall and have a shape extending substantially along a rotation path of a corresponding blade. The mower apparatus also includes a first auxiliary plate and a second auxiliary plate. A portion of the second auxiliary plate and the first auxiliary plate extend parallel to each other such that an opening that is opposed to a mowed grass discharge opening is formed by the rearward ends of the linear portion and the first auxiliary plate. The lower edges of the first and second auxiliary plates are closer to the top plate than the corresponding blade.
