A self-loading feed mixer and transport wagon is provided which is capable of grinding and loading a stack of livestock feed material into the wagon, thoroughly mixing the feed material together, and transporting the feed material to a desired location where it is dispensed from the wagon. The wagon includes a feed grinding and loading mechanism which is vertically adjustable to engage the stack of feed material at different levels. The feed grinding and loading mechanism comprises an open-faced housing which contains a rotatable shaft provided with a plurality of hammer units and a concave screen spaced from the shaft and cooperable with the hammer units to grind the feed material. The grinding and loading mechanism includes a grapple fork pivotally mounted on the housing and adapted to urge the feed material through the open-faced housing into engagement with the pulverizing hammers. The grapple fork is provided with a shield which serves as a protective cover to close the open-faced housing. The ground feed material is fed via a blower unit and flexible spout into the feed compartment of the wagon. Preferably, an auger mechanism is provided at the top of the feed compartment which uniformly distributes the ground feed material along the compartment.