A processing apparatus includes a chuck table for holding a workpiece that has a mark representing a crystal orientation, a processing unit, a cassette stage for placing thereon a cassette for storing a plurality of workpieces therein, a temporary rest table, a spinner table, a robot for delivering a workpiece, a determining section for determining whether a workpiece has been properly processed or has not been properly processed, and a control unit for performing a control process for orienting the mark of the workpiece in a predetermined direction if the determining section determines that the workpiece has been properly processed and storing the workpiece in the cassette, and performing a control process for orienting the mark of the workpiece in a direction different from the predetermined direction if the determining section determines that the workpiece has not been properly processed and storing the workpiece in the cassette.