Abstract: A method of inserting electronic components to a printed circuit board including steps of (a) holding a pair of lead wires of an electronic component by a chuck, which is open-and closable in a perpendicular direction to a plane including the pair of lead wires, with an inter-lead-wire distance identical to the distance between the lead wire inserting holes in the printed circuit board; (b) inserting thus held lead wires into targeted lead wire inserting holes; and (c) applying a clinching treatment to the lead wires protruded to the back side of the printed circuited board, wherein an electronic component is, regardless of the size of the inter-lead-wire distance, held by a chuck such that one of the lead wires is located at a certain preset base position biased to either side of the chucking surface of the chuck, and the printed circuit board and the chuck are relatively positioned, when the lead wires held by the chuck are about to be inserted, such that already inserted (planted) components are positioned