This invention is directed to prevention of reduction of a pickup rate of an electronic component when a component feeding unit is dismounted from a feeder base and mounted back thereon. A CPU sends a feeding command to a component feeding unit feeding an electronic component belonging to a first step number, and drives a servomotor and a drive motor of the feeding unit to perform a component feeding operation and so on. After then, when the CPU judges that the feeding unit is dismounted from the feeder base and mounted back thereon, the CPU drives a X axis drive motor and a Y axis drive motor to move a board recognition camera to the pickup position of the feeding unit, the camera takes an image of a storage portion of a storage tape, and a recognition processing device performs recognition processing to the image. A correction value based on this recognition result is stored in a RAM, the X axis drive motor and the Y axis drive motor are driven taking this correction value into account, a vertical axis drive motor is driven, and a suction nozzle lowers and picks up the electronic component.