PURPOSE: To comply with the dislocation of a suction nozzle in a real-time manner and to mount an electronic component on an accurate position by using a method wherein the image of the electronic component sucked to the suction nozzle is picked up, its positional data and its angle of rotation are found and the position of the electronic components is corrected on the basis of them.

CONSTITUTION: The image of the posture of an electronic component 1 using a first pickup camera 17; the positional data and the angle of rotation of the electronic component 1 are operated by an operation control part 20. Then, a rotation drive means 21 corrects the posture of the electronic components 1 by the instruction of the operation control part 20. The operation control part 20 operates and finds the positional data (G1) of the electronic component 1 after the correction. The image of the electronic component 1 after the correction is picked up by using a second image pickup camera 25; its positional data (G2) is found. The operation control part 20 compares the positional data G1 with the positional data G2. When they differ, the same action is repeated. Thereby, the electronic component 1 can be positioned and mounted on a circuit board 29 with high accuracy.