An apparatus and method for transforming NC programs are provided, and the apparatus is electrically connected to a controller configured to, according to a NC program, command a machine to drive a cutting tool to cut a workpiece. The apparatus includes a triggering module, a coordinate position processing module, and a storage module. The triggering module is electrically connected to the controller. The coordinate position processing module is electrically connected to the controller and the triggering module. The storage module is electrically connected to the coordinate position processing module. The triggering module triggers the controller to execute the NC program in a single block mode. The coordinate position processing module is triggered by the triggering module to acquire at least one coordinate position from the controller. The storage module stores the at least one coordinate position. The triggering module simultaneously triggers the controller and the coordinate position processing module.